:root {
    --red: #e50914;
    --red-dark: #b20710;
    --ink: #20242b;
    --muted: #747b86;
    --line: #e4e7ec;
    --surface: #ffffff;
    --page: #f3f4f6;
    --sidebar: #15181d;
}

* { box-sizing: border-box; }

html, body { min-height: 100%; }

body {
    margin: 0;
    color: var(--ink);
    background: var(--page);
    font-family: "DM Sans", sans-serif;
}

button, input, select { font: inherit; }
button, a { -webkit-tap-highlight-color: transparent; }

.tracker-wordmark {
    color: #fff;
    font-family: "Plus Jakarta Sans", sans-serif;
    font-size: 1.35rem;
    font-weight: 900;
    letter-spacing: .04em;
}

.tracker-wordmark > span { color: var(--red); }
.tracker-wordmark em { margin-left: 5px; color: #8d949f; font-size: .55rem; font-style: normal; letter-spacing: .15em; }

.tracker-login-body { overflow-x: hidden; background: #10141a; }

.tracker-login-page {
    min-height: 100vh;
    min-height: 100svh;
    padding: 28px;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    overflow: hidden;
    background:
        radial-gradient(circle at 82% 14%, rgba(229, 9, 20, .2), transparent 28%),
        radial-gradient(circle at 12% 88%, rgba(229, 9, 20, .09), transparent 34%),
        linear-gradient(140deg, #07090c, #151922);
}

.tracker-login-glow { width: 520px; height: 520px; position: absolute; top: -250px; right: -120px; border-radius: 50%; background: rgba(229, 9, 20, .28); filter: blur(80px); }

.tracker-login-card {
    width: min(480px, 100%);
    padding: 30px 34px 34px;
    position: relative;
    border: 1px solid rgba(255, 255, 255, .14);
    border-radius: 24px;
    color: #fff;
    background: rgba(20, 23, 29, .91);
    box-shadow: 0 36px 100px rgba(0, 0, 0, .45);
    backdrop-filter: blur(18px);
}

.tracker-login-brand-row { display: flex; align-items: center; justify-content: space-between; gap: 18px; }
.tracker-login-icon { width: 50px; height: 50px; flex: 0 0 50px; border-radius: 15px; display: grid; place-items: center; color: #fff; background: var(--red); box-shadow: 0 14px 32px rgba(229, 9, 20, .32); font-size: 1.35rem; }
.tracker-login-card h1 { margin: 24px 0 10px; color: #fff; font-family: "Plus Jakarta Sans", sans-serif; font-size: clamp(1.75rem, 5vw, 2.4rem); line-height: 1.1; }
.tracker-login-card > p { margin: 0 0 25px; color: #aeb4bf; line-height: 1.65; }
.tracker-login-form { display: grid; gap: 14px; }
.tracker-login-form label { display: grid; gap: 7px; color: #d9dce2; font-size: .78rem; font-weight: 800; }
.tracker-login-form input { width: 100%; min-height: 49px; padding: 0 14px; border: 1px solid rgba(255, 255, 255, .13); border-radius: 11px; color: #fff; outline: 0; background: rgba(255, 255, 255, .07); }
.tracker-login-form input:focus { border-color: rgba(229, 9, 20, .8); box-shadow: 0 0 0 3px rgba(229, 9, 20, .12); }
.tracker-login-message { min-height: 18px; margin: -4px 0; color: #aeb4bf; font-size: .76rem; }
.tracker-login-message.is-error { color: #ff8088; }
.tracker-login-form button, .tracker-primary-link { min-height: 50px; border: 0; border-radius: 11px; display: flex; align-items: center; justify-content: center; gap: 10px; color: #fff; background: var(--red); font-weight: 900; cursor: pointer; text-decoration: none; }
.tracker-login-form button:disabled, .tracker-google-login.is-loading { opacity: .72; cursor: wait; pointer-events: none; }
.tracker-forgot-password { margin-top: 15px; display: inline-block; color: #aeb4bf; font-size: .86rem; font-weight: 700; text-decoration: none; }
.tracker-login-divider { margin: 22px 0; display: flex; align-items: center; gap: 12px; color: #777e89; font-size: .72rem; }
.tracker-login-divider::before, .tracker-login-divider::after { content: ""; height: 1px; flex: 1; background: rgba(255, 255, 255, .11); }
.tracker-google-login { min-height: 49px; border: 1px solid rgba(255, 255, 255, .14); border-radius: 11px; display: flex; align-items: center; justify-content: center; gap: 10px; color: #fff; background: rgba(255, 255, 255, .07); font-weight: 800; text-decoration: none; }
.tracker-eyebrow { margin: 0 0 7px; color: var(--red); font-size: .72rem; font-weight: 800; letter-spacing: .13em; text-transform: uppercase; }
.tracker-login-card .tracker-eyebrow { margin-top: 27px; margin-bottom: 0; color: #ff5962; }

.tracker-shell { min-height: 100vh; }
[hidden] { display: none !important; }
.tracker-menu-open { overflow: hidden; }

.tracker-sidebar {
    width: 278px;
    height: 100vh;
    height: 100dvh;
    padding: 28px 20px 22px;
    position: fixed;
    z-index: 23000;
    inset: 0 auto 0 0;
    display: flex;
    flex-direction: column;
    overflow-y: auto;
    color: #fff;
    background: radial-gradient(circle at 0 0, rgba(229, 9, 20, .17), transparent 30%), var(--sidebar);
    box-shadow: 16px 0 45px rgba(10, 13, 18, .16);
    transform: translateX(-105%);
    transition: transform .24s ease;
}
.tracker-sidebar.is-open { transform: translateX(0); }
.tracker-sidebar-close { width: 38px; height: 38px; position: absolute; top: 20px; right: 17px; border: 0; border-radius: 10px; display: grid; place-items: center; color: #aeb4bd; background: rgba(255, 255, 255, .07); cursor: pointer; }
.tracker-sidebar-close:hover { color: #fff; background: rgba(255, 255, 255, .12); }
.tracker-sidebar-backdrop { position: fixed; z-index: 22500; inset: 0; border: 0; background: rgba(9, 11, 15, .56); backdrop-filter: blur(2px); cursor: default; }

.tracker-nav { margin-top: 58px; display: grid; gap: 9px; }
.tracker-nav-label { padding: 0 12px; color: #737a85; font-size: .65rem; font-weight: 800; letter-spacing: .13em; text-transform: uppercase; }
.tracker-nav button { width: 100%; min-height: 50px; padding: 0 12px; border: 1px solid transparent; border-radius: 12px; display: grid; grid-template-columns: 25px minmax(0, 1fr) auto; align-items: center; gap: 8px; color: #d9dce2; background: transparent; font-weight: 800; text-align: left; cursor: pointer; }
.tracker-nav button:hover, .tracker-nav button.is-active { border-color: rgba(229, 9, 20, .28); color: #fff; background: rgba(229, 9, 20, .12); }
.tracker-nav button i { color: var(--red); }
.tracker-nav button strong { min-width: 28px; height: 28px; padding: 0 8px; border-radius: 9px; display: grid; place-items: center; color: #fff; background: rgba(255, 255, 255, .1); font-size: .72rem; }

.student-gallery { padding: 26px; border: 1px solid var(--line); border-radius: 20px; display: flex; flex-wrap: wrap; justify-content: center; align-items: flex-start; gap: 30px 34px; background: rgba(255, 255, 255, .76); box-shadow: 0 12px 35px rgba(25, 28, 33, .05); }
.student-tile { --student-color: #e50914; --student-color-dark: #a60710; width: 128px; min-width: 0; flex: 0 1 128px; padding: 13px 8px; border: 1px solid transparent; border-radius: 16px; display: grid; justify-items: center; gap: 11px; color: #3d424a; background: transparent; cursor: pointer; transition: .18s ease; }
.student-tile:hover, .student-tile:focus-visible { border-color: rgba(229, 9, 20, .22); color: var(--red-dark); background: #fff; box-shadow: 0 12px 28px rgba(22, 26, 31, .08); transform: translateY(-3px); outline: 0; }
.student-tile.is-active { color: var(--red-dark); }
.student-tile[data-color="orange"] { --student-color: #f07818; --student-color-dark: #b9580e; }
.student-tile[data-color="yellow"] { --student-color: #d6a20d; --student-color-dark: #9d7504; }
.student-tile[data-color="green"] { --student-color: #20a768; --student-color-dark: #137645; }
.student-tile[data-color="blue"] { --student-color: #3979df; --student-color-dark: #2452a0; }
.student-tile[data-color="purple"] { --student-color: #8a55ce; --student-color-dark: #603697; }
.student-tile[data-color="gray"] { --student-color: #8b929d; --student-color-dark: #5f6670; }
.student-avatar { width: 94px; height: 94px; border: 3px solid #fff; border-radius: 50%; display: grid; place-items: center; overflow: hidden; color: #fff; background: linear-gradient(145deg, var(--student-color), var(--student-color-dark)); box-shadow: 0 0 0 2px var(--student-color), 0 10px 24px rgba(22, 26, 31, .14); font-size: 1.15rem; font-weight: 900; }
.student-tile:hover .student-avatar, .student-tile:focus-visible .student-avatar { box-shadow: 0 0 0 3px var(--student-color), 0 14px 28px rgba(22, 26, 31, .17); }
.student-tile.is-unconnected { color: #777e88; }
.student-tile.is-unconnected .student-avatar { color: #f4f5f7; background: linear-gradient(145deg, #9ba1aa, #5f6670); box-shadow: 0 0 0 2px #aeb4bd, 0 10px 24px rgba(22, 26, 31, .12); }
.student-tile.is-unconnected:hover .student-avatar, .student-tile.is-unconnected:focus-visible .student-avatar { box-shadow: 0 0 0 3px #8b929d, 0 14px 28px rgba(22, 26, 31, .15); }
.student-avatar img { width: 100%; height: 100%; object-fit: cover; }
.student-tile-name { width: 100%; min-width: 0; display: grid; gap: 2px; font-size: .82rem; font-weight: 800; text-align: center; }
.student-tile-name > span { min-width: 0; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.student-tile-name > small { overflow: hidden; color: #8a919b; font-size: .7rem; font-weight: 800; text-overflow: ellipsis; white-space: nowrap; }

.tracker-account { margin-top: auto; padding-top: 17px; border-top: 1px solid rgba(255, 255, 255, .1); display: grid; grid-template-columns: 38px minmax(0, 1fr) 30px; align-items: center; gap: 10px; }
.tracker-account-avatar { width: 38px; height: 38px; border-radius: 50%; display: grid; place-items: center; color: #fff; background: var(--red); font-weight: 900; }
.tracker-account div { min-width: 0; display: grid; gap: 2px; }
.tracker-account strong, .tracker-account small { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.tracker-account strong { color: #fff; font-size: .78rem; }
.tracker-account small { color: #7f8690; font-size: .62rem; }
.tracker-account a { width: 30px; height: 30px; border-radius: 9px; display: grid; place-items: center; color: #9299a4; text-decoration: none; }
.tracker-account a:hover { color: #fff; background: rgba(255, 255, 255, .08); }

.tracker-main { min-width: 0; padding: 26px clamp(22px, 4vw, 58px) 48px; }
.tracker-toolbar { margin-bottom: 36px; display: flex; align-items: center; gap: 13px; }
.tracker-board-open .tracker-toolbar { margin-bottom: 16px; }
.tracker-menu-button { width: 44px; height: 44px; flex: 0 0 44px; border: 1px solid #dfe2e7; border-radius: 12px; display: grid; place-items: center; color: #353a42; background: #fff; box-shadow: 0 5px 17px rgba(20, 24, 30, .06); cursor: pointer; }
.tracker-menu-button:hover { border-color: rgba(229, 9, 20, .45); color: var(--red); }
.tracker-toolbar-wordmark { color: #24282f; font-family: "Plus Jakarta Sans", sans-serif; font-size: 1.1rem; font-weight: 900; letter-spacing: .04em; }
.tracker-toolbar-wordmark > span { color: var(--red); }
.tracker-toolbar-wordmark em { margin-left: 5px; color: #8d949f; font-size: .48rem; font-style: normal; letter-spacing: .15em; }
.tracker-toolbar-student { min-width: 0; padding-left: 13px; border-left: 1px solid #d8dce2; display: flex; align-items: center; gap: 10px; }
.tracker-toolbar-student button { width: 30px; height: 30px; flex: 0 0 30px; border: 0; border-radius: 8px; display: grid; place-items: center; color: #626974; background: #e7e9ed; cursor: pointer; }
.tracker-toolbar-student button:hover { color: #fff; background: var(--red); }
.tracker-toolbar-student > strong { min-width: 0; overflow: hidden; color: #22262d; font-family: "Plus Jakarta Sans", sans-serif; font-size: 1.05rem; text-overflow: ellipsis; white-space: nowrap; }
.toolbar-student-code { min-height: 32px; padding: 0 4px 0 9px; border: 1px solid rgba(229, 9, 20, .25); border-radius: 9px; position: relative; display: flex; align-items: center; gap: 7px; color: #9b1119; background: rgba(229, 9, 20, .055); white-space: nowrap; }
.toolbar-student-code > span:first-child { color: #9b1119; font-size: .62rem; font-weight: 900; text-transform: uppercase; letter-spacing: .06em; }
.toolbar-student-code > strong { color: #b20710; font-family: "Plus Jakarta Sans", sans-serif; font-size: .76rem; letter-spacing: .09em; }
.toolbar-student-code > button { width: 25px; height: 25px; border: 0; border-radius: 7px; display: grid; place-items: center; color: #9b1119; background: #fff; cursor: pointer; }
.toolbar-student-code > button:hover { color: #fff; background: var(--red); }
.toolbar-student-code-tooltip { width: 330px; padding: 10px 12px; position: absolute; z-index: 40; top: calc(100% + 9px); left: 0; border-radius: 9px; color: #fff; background: #24282f; box-shadow: 0 12px 30px rgba(17, 20, 25, .24); font-size: .72rem; font-weight: 750; line-height: 1.5; white-space: normal; opacity: 0; visibility: hidden; transform: translateY(-5px); pointer-events: none; transition: opacity .16s ease, transform .16s ease, visibility .16s ease; }
.toolbar-student-code-tooltip::before { content: ""; width: 10px; height: 10px; position: absolute; top: -5px; left: 20px; background: #24282f; transform: rotate(45deg); }
.toolbar-student-code:hover .toolbar-student-code-tooltip, .toolbar-student-code:focus-within .toolbar-student-code-tooltip { opacity: 1; visibility: visible; transform: translateY(0); }
.tracker-toolbar .save-indicator { margin-left: auto; }
.students-view { width: 100%; max-width: 1050px; margin-inline: auto; }
.tracker-view { width: 100%; }
.students-view-header { margin-bottom: 26px; display: flex; align-items: flex-end; justify-content: space-between; gap: 24px; }
.students-view-header h1 { margin: 0; font-family: "Plus Jakarta Sans", sans-serif; font-size: clamp(1.9rem, 3.5vw, 2.7rem); letter-spacing: -.04em; }
.students-view-header div > p:last-child { margin: 8px 0 0; color: var(--muted); }
.students-total { padding: 10px 13px; border: 1px solid #dfe2e7; border-radius: 11px; color: #747b86; background: #fff; font-size: .74rem; font-weight: 700; white-space: nowrap; }
.students-total strong { color: var(--red); }
.students-header-actions { display: flex; align-items: center; gap: 9px; }
.teacher-code-pill { min-height: 38px; padding: 0 5px 0 12px; border: 1px solid rgba(229, 9, 20, .22); border-radius: 11px; position: relative; display: flex; align-items: center; gap: 8px; color: #747b86; background: rgba(229, 9, 20, .045); white-space: nowrap; }
.teacher-code-pill > span:not(.teacher-code-tooltip) { font-size: .67rem; font-weight: 800; text-transform: uppercase; letter-spacing: .06em; }
.teacher-code-pill > strong { color: #b20710; font-family: "Plus Jakarta Sans", sans-serif; font-size: .86rem; letter-spacing: .09em; }
.teacher-code-pill button { width: 30px; height: 30px; border: 0; border-radius: 8px; display: grid; place-items: center; color: #9b1119; background: #fff; cursor: pointer; }
.teacher-code-pill button:hover { color: #fff; background: var(--red); }
.teacher-code-tooltip { width: 290px; padding: 10px 12px; position: absolute; z-index: 30; right: 0; bottom: calc(100% + 9px); border-radius: 9px; color: #fff; background: #24282f; box-shadow: 0 12px 30px rgba(17, 20, 25, .22); font-size: .72rem; font-weight: 700; line-height: 1.5; white-space: normal; opacity: 0; visibility: hidden; transform: translateY(5px); pointer-events: none; transition: opacity .16s ease, transform .16s ease, visibility .16s ease; }
.teacher-code-tooltip::after { content: ""; width: 10px; height: 10px; position: absolute; right: 18px; bottom: -5px; background: #24282f; transform: rotate(45deg); }
.teacher-code-pill:hover .teacher-code-tooltip, .teacher-code-pill:focus-within .teacher-code-tooltip { opacity: 1; visibility: visible; transform: translateY(0); }
.add-student-button { min-height: 38px; padding: 0 14px; border: 1px solid var(--red); border-radius: 11px; color: #fff; background: var(--red); font-size: .75rem; font-weight: 800; cursor: pointer; }
.add-student-button:hover { background: var(--red-dark); }
.add-student-button i { margin-right: 5px; }
.back-to-students { margin: 0 0 10px; padding: 0; border: 0; color: #676e78; background: transparent; font-size: .78rem; font-weight: 800; cursor: pointer; }
.back-to-students:hover { color: var(--red); }
.back-to-students i { margin-right: 6px; }
.tracker-header { margin-bottom: 18px; display: flex; align-items: flex-end; justify-content: space-between; gap: 24px; }
.tracker-header h1 { margin: 0; font-family: "Plus Jakarta Sans", sans-serif; font-size: clamp(1.75rem, 3vw, 2.5rem); letter-spacing: -.035em; }
.tracker-header .tracker-eyebrow { margin-bottom: 3px; }
.save-indicator { padding: 9px 12px; border: 1px solid #dfe2e7; border-radius: 10px; display: flex; align-items: center; gap: 7px; color: #717883; background: #fff; box-shadow: 0 5px 18px rgba(20, 24, 30, .05); font-size: .72rem; font-weight: 700; white-space: nowrap; }
.save-indicator > span { width: 7px; height: 7px; border-radius: 50%; background: #20af68; }
.save-indicator.is-saving { color: var(--red-dark); }

.tracker-board { min-height: calc(100vh - 112px); display: grid; grid-template-columns: repeat(3, minmax(240px, 1fr)); gap: 18px; align-items: stretch; }
.board-column { min-width: 0; padding: 18px; border: 1px solid #e2e5e9; border-top: 4px solid #d9dce1; border-radius: 16px; background: rgba(255, 255, 255, .82); box-shadow: 0 12px 32px rgba(25, 28, 33, .055); transition: border-color .18s ease, background-color .18s ease, transform .18s ease; }
.board-column[data-status="preparing"] { border-top-color: #e50914; }
.board-column.is-featured { border-top-color: #f59e0b; background: linear-gradient(180deg, rgba(245, 158, 11, .045), rgba(255, 255, 255, .9) 110px); }
.board-column[data-status="completed"] { border-top-color: #22c55e; }
.board-column.is-drag-over { border-color: rgba(229, 9, 20, .46); background: rgba(229, 9, 20, .035); transform: translateY(-2px); }
.board-column > header { min-height: 39px; display: flex; align-items: flex-start; justify-content: space-between; gap: 12px; }
.board-column > header > div { display: flex; align-items: center; gap: 9px; }
.column-dot { width: 9px; height: 9px; border-radius: 50%; background: #c8ccd2; }
.board-column[data-status="preparing"] .column-dot { background: #e50914; box-shadow: 0 0 0 5px rgba(229, 9, 20, .08); }
.board-column[data-status="studying"] .column-dot { background: #f59e0b; box-shadow: 0 0 0 5px rgba(245, 158, 11, .1); }
.board-column[data-status="completed"] .column-dot { background: #22c55e; box-shadow: 0 0 0 5px rgba(34, 197, 94, .09); }
.board-column h2 { margin: 0; font-family: "Plus Jakarta Sans", sans-serif; font-size: 1.05rem; }
.board-column header strong { min-width: 25px; height: 25px; padding: 0 7px; border-radius: 8px; display: grid; place-items: center; color: #6e7580; background: #eceef1; font-size: .72rem; }
.column-info { width: 29px; height: 29px; border: 1px solid #e0e3e7; border-radius: 50%; display: grid; place-items: center; color: #8a919b; background: #fff; font-size: .65rem; }

.add-lesson-button { width: 100%; min-height: 45px; margin: 5px 0 12px; border: 1px dashed rgba(229, 9, 20, .38); border-radius: 11px; color: var(--red-dark); background: rgba(229, 9, 20, .035); font-weight: 800; cursor: pointer; }
.add-lesson-button:hover { border-color: var(--red); background: rgba(229, 9, 20, .07); }
.add-lesson-form { margin: 5px 0 12px; padding: 13px; border: 1px solid rgba(229, 9, 20, .25); border-radius: 12px; background: #fff; box-shadow: 0 8px 25px rgba(25, 28, 33, .07); }
.add-lesson-form[hidden] { display: none; }
.add-lesson-form button { min-height: 34px; padding: 0 11px; border: 1px solid #dfe2e7; border-radius: 8px; color: #555c66; background: #fff; font-size: .7rem; font-weight: 800; cursor: pointer; }
.add-lesson-form button[type="submit"] { border-color: var(--red); color: #fff; background: var(--red); }
.lesson-source-choice { display: grid; grid-template-columns: 1fr 1fr; gap: 8px; }
.lesson-source-choice > button { min-width: 0; min-height: 82px; padding: 10px 7px; display: grid; place-items: center; align-content: center; gap: 3px; text-align: center; }
.lesson-source-choice > button:hover { border-color: var(--red); color: var(--red-dark); background: rgba(229, 9, 20, .035); }
.lesson-source-choice > button > span { width: 28px; height: 28px; border-radius: 8px; display: grid; place-items: center; color: #fff; background: var(--red); font-size: .75rem; }
.lesson-source-choice strong { overflow: hidden; max-width: 100%; font-size: .72rem; text-overflow: ellipsis; white-space: nowrap; }
.lesson-source-choice small { color: #969ca5; font-size: .58rem; font-weight: 700; line-height: 1.25; }
.lesson-source-cancel { width: 100%; margin-top: 8px; color: #7c838d !important; background: #f5f6f7 !important; }
.generated-lesson-picker > header { min-height: 30px; margin-bottom: 8px; display: flex; align-items: center; gap: 7px; }
.generated-lesson-picker > header button, .add-lesson-back { width: 28px; min-height: 28px !important; padding: 0 !important; border: 0 !important; color: #6f7680 !important; background: #f0f2f4 !important; }
.generated-lesson-picker > header strong { min-width: 0; height: auto; padding: 0; border-radius: 0; display: block; overflow: hidden; color: #30343a; background: transparent; font-size: .72rem; text-overflow: ellipsis; white-space: nowrap; }
.generated-lesson-list { max-height: 292px; overflow-y: auto; display: grid; gap: 6px; scrollbar-width: thin; }
.generated-lesson-option { width: 100%; min-height: 55px !important; padding: 7px 8px !important; display: grid; grid-template-columns: 32px minmax(0, 1fr) 20px; align-items: center; gap: 8px; text-align: left; }
.generated-lesson-option:hover { border-color: var(--red); background: rgba(229, 9, 20, .025); }
.generated-lesson-option:disabled { opacity: .55; cursor: wait; }
.generated-lesson-option.is-adding { border-color: var(--red); opacity: 1; background: rgba(229, 9, 20, .05); }
.generated-lesson-icon { width: 32px; height: 32px; border-radius: 9px; display: grid; place-items: center; color: var(--red); background: rgba(229, 9, 20, .08); font-size: .78rem; }
.generated-lesson-option[data-lesson-type="reading"] .generated-lesson-icon { color: #3979df; background: rgba(57, 121, 223, .1); }
.generated-lesson-option[data-lesson-type="vocabulary"] .generated-lesson-icon { color: #8a55ce; background: rgba(138, 85, 206, .1); }
.generated-lesson-option[data-lesson-type="youtube"] .generated-lesson-icon { color: #e50914; background: rgba(229, 9, 20, .08); }
.generated-lesson-option[data-lesson-type="grammar"] .generated-lesson-icon { color: #20a768; background: rgba(32, 167, 104, .1); }
.generated-lesson-copy { min-width: 0; display: grid; gap: 2px; }
.generated-lesson-copy strong, .generated-lesson-copy small { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.generated-lesson-copy strong { color: #30343a; font-size: .7rem; }
.generated-lesson-copy small { color: #9298a1; font-size: .57rem; }
.generated-lesson-option > i { color: #a2a8b0; font-size: .65rem; }
.generated-lessons-state { min-height: 115px; padding: 15px; border: 1px dashed #dde1e6; border-radius: 9px; display: grid; place-items: center; align-content: center; gap: 7px; color: #949aa4; font-size: .65rem; font-weight: 700; text-align: center; }
.generated-lessons-state.is-error { color: var(--red-dark); }
.other-lesson-entry { display: grid; }
.add-lesson-back { width: auto; margin-bottom: 8px; padding: 0 9px !important; justify-self: start; }
.other-lesson-entry label { display: block; margin-bottom: 6px; color: #6f7680; font-size: .69rem; font-weight: 800; }
.other-lesson-entry input { width: 100%; min-height: 42px; padding: 0 11px; border: 1px solid #dce0e5; border-radius: 9px; outline: 0; }
.other-lesson-entry input:focus { border-color: var(--red); box-shadow: 0 0 0 3px rgba(229, 9, 20, .08); }
.other-lesson-entry > div { margin-top: 9px; display: flex; justify-content: flex-end; gap: 7px; }

.lesson-list { min-height: 315px; display: flex; flex-direction: column; gap: 11px; }
.lesson-card { --card-color: #e50914; --card-tint: rgba(229, 9, 20, .07); min-height: 54px; padding: 10px 12px; border: 1px solid #e5e7eb; border-left: 4px solid var(--card-color); border-radius: 12px; display: grid; grid-template-columns: 28px minmax(0, 1fr) 28px; align-items: center; gap: 10px; background: #fff; box-shadow: 0 7px 20px rgba(22, 26, 31, .07); cursor: grab; transition: opacity .15s ease, transform .15s ease, box-shadow .15s ease; }
.lesson-card.has-progress { padding-bottom: 15px; position: relative; overflow: hidden; }
.lesson-card:hover { transform: translateY(-2px); box-shadow: 0 12px 25px rgba(22, 26, 31, .1); }
.lesson-card.is-dragging { opacity: .42; cursor: grabbing; transform: rotate(1deg) scale(.98); }
.lesson-card[data-color="orange"] { --card-color: #f07818; --card-tint: rgba(240, 120, 24, .11); }
.lesson-card[data-color="yellow"] { --card-color: #d6a20d; --card-tint: rgba(214, 162, 13, .12); }
.lesson-card[data-color="green"] { --card-color: #20a768; --card-tint: rgba(32, 167, 104, .1); }
.lesson-card[data-color="blue"] { --card-color: #3979df; --card-tint: rgba(57, 121, 223, .1); }
.lesson-card[data-color="purple"] { --card-color: #8a55ce; --card-tint: rgba(138, 85, 206, .1); }
.lesson-card[data-color="gray"] { --card-color: #8b929d; --card-tint: rgba(139, 146, 157, .12); }
.lesson-icon { width: 28px; height: 28px; border-radius: 8px; display: grid; place-items: center; color: var(--card-color); background: var(--card-tint); font-size: .8rem; }
.lesson-expand { width: 28px; height: 28px; padding: 0; border: 0; border-radius: 8px; display: grid; place-items: center; color: #939aa4; background: #f0f2f4; cursor: pointer; }
.lesson-expand:hover, .lesson-expand:focus-visible { color: #fff; background: var(--card-color); outline: 0; }
.lesson-expand i { transition: transform .18s ease; }
.lesson-expand[aria-expanded="true"] i { transform: rotate(180deg); }
.lesson-card h3 { min-width: 0; margin: 0; overflow: hidden; color: #272b32; font-family: "Plus Jakarta Sans", sans-serif; font-size: .88rem; line-height: 1.4; text-overflow: ellipsis; white-space: nowrap; }
.lesson-card-details { padding: 10px 0 1px 38px; border-top: 1px solid #eceef1; grid-column: 1 / -1; display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 10px; }
.lesson-card-details > div { min-width: 0; display: grid; gap: 2px; }
.lesson-card-details span { color: #9a9fa8; font-size: .6rem; font-weight: 800; text-transform: uppercase; letter-spacing: .06em; }
.lesson-card-details strong { overflow: hidden; color: #555c66; font-size: .69rem; text-overflow: ellipsis; white-space: nowrap; }
.lesson-card-details .lesson-notes { margin-top: 2px; grid-column: 1 / -1; display: block; }
.lesson-notes-header { margin-bottom: 5px; display: flex; align-items: center; justify-content: space-between; gap: 10px; }
.lesson-notes-header label { color: #777e88; font-size: .62rem; font-weight: 800; text-transform: uppercase; letter-spacing: .06em; }
.lesson-notes-header small { color: #22a662; font-size: .58rem; font-weight: 800; }
.lesson-notes-header small.is-error { color: #d71920; }
.lesson-notes textarea { width: 100%; min-height: 72px; padding: 9px 10px; border: 1px solid #dde1e6; border-radius: 8px; display: block; color: #3e444c; background: #fafbfc; font-family: "DM Sans", sans-serif; font-size: .69rem; line-height: 1.45; resize: vertical; outline: 0; cursor: text; }
.lesson-notes textarea:focus { border-color: var(--card-color); background: #fff; box-shadow: 0 0 0 3px var(--card-tint); }
.lesson-notes textarea::placeholder { color: #a1a7b0; }
.lesson-open-link { min-height: 30px; padding: 0 9px; border-radius: 7px; grid-column: 1 / -1; display: flex; align-items: center; justify-content: center; gap: 6px; color: var(--card-color); background: var(--card-tint); font-size: .65rem; font-weight: 800; text-decoration: none; }
.lesson-open-link:hover { color: #fff; background: var(--card-color); }
.lesson-progress { height: 6px; position: absolute; right: 0; bottom: 0; left: 0; display: flex; overflow: hidden; background: #d7dbe0; }
.lesson-progress span { height: 100%; flex: 0 0 auto; transition: width .25s ease; }
.lesson-progress .is-correct { background: #22c55e; }
.lesson-progress .is-incorrect { background: #ef4444; }
.lesson-progress .is-missing { background: #d7dbe0; }
.column-empty { min-height: 185px; padding: 25px 14px; border: 1px dashed #dfe2e6; border-radius: 12px; display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 7px; color: #a0a6af; text-align: center; }
.tracker-board.is-dragging-lesson .column-empty { display: none; }
.column-empty i { width: 34px; height: 34px; border-radius: 50%; display: grid; place-items: center; color: #c0c5cc; background: #f2f3f5; font-size: .72rem; }
.column-empty strong { color: #858b94; font-size: .76rem; }
.column-empty span { max-width: 180px; font-size: .66rem; line-height: 1.5; }
.lesson-skeleton { height: 112px; border-radius: 12px; background: linear-gradient(90deg, #eceef1 25%, #f7f8f9 50%, #eceef1 75%); background-size: 200% 100%; animation: tracker-shimmer 1.1s infinite linear; }
@keyframes tracker-shimmer { to { background-position: -200% 0; } }

.empty-classroom { min-height: 480px; border: 1px dashed #d6dae0; border-radius: 18px; display: grid; place-content: center; justify-items: center; padding: 35px; text-align: center; background: rgba(255, 255, 255, .65); }
.empty-classroom > span { width: 65px; height: 65px; border-radius: 20px; display: grid; place-items: center; color: #fff; background: var(--red); box-shadow: 0 14px 28px rgba(229, 9, 20, .2); font-size: 1.35rem; }
.empty-classroom h2 { margin: 20px 0 7px; font-family: "Plus Jakarta Sans", sans-serif; }
.empty-classroom p { max-width: 410px; margin: 0; color: var(--muted); line-height: 1.6; }

.tracker-modal { position: fixed; z-index: 24000; inset: 0; display: grid; place-items: center; padding: 20px; }
.tracker-modal-backdrop { position: absolute; inset: 0; border: 0; background: rgba(10, 12, 16, .62); backdrop-filter: blur(3px); }
.tracker-modal-card { width: min(430px, 100%); padding: 28px; position: relative; z-index: 1; border-radius: 20px; background: #fff; box-shadow: 0 30px 85px rgba(0, 0, 0, .3); }
.add-lesson-modal-card { width: min(620px, 100%); max-height: min(760px, calc(100vh - 40px)); display: flex; flex-direction: column; }
.add-lesson-modal-card .add-lesson-form { min-height: 0; margin: 8px 0 0; padding: 0; border: 0; border-radius: 0; background: transparent; box-shadow: none; }
.add-lesson-modal-card .lesson-source-choice { margin-top: 0; display: grid; grid-template-columns: 1fr 1fr; gap: 10px; }
.add-lesson-modal-card .lesson-source-choice > button { min-height: 108px; }
.add-lesson-modal-card .generated-lesson-list { max-height: min(480px, calc(100vh - 245px)); }
.add-lesson-modal-card .generated-lesson-option { min-height: 62px !important; padding: 9px 10px !important; }
.add-lesson-modal-card .generated-lesson-icon { color: #e50914 !important; background: rgba(229, 9, 20, .08) !important; }
.add-lesson-modal-card .generated-lesson-copy strong { font-size: .78rem; }
.add-lesson-modal-card .generated-lesson-copy small { font-size: .62rem; }
.tracker-modal-close { width: 34px; height: 34px; position: absolute; top: 16px; right: 16px; border: 0; border-radius: 9px; display: grid; place-items: center; color: #707782; background: #eff1f3; cursor: pointer; }
.tracker-modal-icon { width: 44px; height: 44px; border-radius: 13px; display: grid; place-items: center; color: #fff; background: var(--red); }
.tracker-modal-card h2 { margin: 18px 0 7px; font-family: "Plus Jakarta Sans", sans-serif; font-size: 1.45rem; }
.tracker-modal-card > p { margin: 0 0 20px; color: var(--muted); font-size: .86rem; line-height: 1.55; }
.tracker-modal-card form { display: grid; gap: 8px; }
.tracker-modal-card label { color: #656c76; font-size: .75rem; font-weight: 800; }
.tracker-modal-card input { width: 100%; min-height: 46px; padding: 0 12px; border: 1px solid #d8dce2; border-radius: 10px; outline: 0; }
.tracker-modal-card input:focus { border-color: var(--red); box-shadow: 0 0 0 3px rgba(229, 9, 20, .08); }
.tracker-modal-card form > div { margin-top: 10px; display: flex; justify-content: flex-end; gap: 8px; }
.tracker-modal-card form button { min-height: 39px; padding: 0 14px; border: 1px solid #d8dce2; border-radius: 9px; color: #59606a; background: #fff; font-weight: 800; cursor: pointer; }
.tracker-modal-card form button[type="submit"] { border-color: var(--red); color: #fff; background: var(--red); }
.tracker-modal-actions { margin-top: 22px; display: flex; justify-content: flex-end; gap: 8px; }
.tracker-modal-actions button { min-height: 40px; padding: 0 14px; border: 1px solid #d8dce2; border-radius: 9px; color: #59606a; background: #fff; font-weight: 800; cursor: pointer; }
.tracker-modal-actions .confirm-remove { border-color: var(--red); color: #fff; background: var(--red); }
.tracker-modal-actions .confirm-remove:hover { background: var(--red-dark); }
.tracker-modal-actions button:disabled { opacity: .65; cursor: wait; }

.lesson-context-menu, .student-context-menu { width: 224px; padding: 12px; position: fixed; z-index: 23500; border: 1px solid #e0e3e7; border-radius: 13px; background: #fff; box-shadow: 0 18px 48px rgba(15, 18, 23, .2); }
.lesson-menu-label { display: block; margin: 0 2px 9px; color: #747b86; font-size: .68rem; font-weight: 800; text-transform: uppercase; letter-spacing: .08em; }
.lesson-colors, .student-colors { display: grid; grid-template-columns: repeat(7, 1fr); gap: 6px; }
.lesson-colors button, .student-colors button { width: 22px; height: 22px; padding: 0; border: 2px solid #fff; border-radius: 50%; background: var(--choice-color); box-shadow: 0 0 0 1px #d8dce2; cursor: pointer; }
.lesson-colors button:hover, .lesson-colors button.is-selected, .student-colors button:hover, .student-colors button.is-selected { box-shadow: 0 0 0 2px #252a31; transform: scale(1.08); }
.lesson-colors [data-lesson-color="red"], .student-colors [data-student-color="red"] { --choice-color: #e50914; }
.lesson-colors [data-lesson-color="orange"], .student-colors [data-student-color="orange"] { --choice-color: #f07818; }
.lesson-colors [data-lesson-color="yellow"], .student-colors [data-student-color="yellow"] { --choice-color: #d6a20d; }
.lesson-colors [data-lesson-color="green"], .student-colors [data-student-color="green"] { --choice-color: #20a768; }
.lesson-colors [data-lesson-color="blue"], .student-colors [data-student-color="blue"] { --choice-color: #3979df; }
.lesson-colors [data-lesson-color="purple"], .student-colors [data-student-color="purple"] { --choice-color: #8a55ce; }
.lesson-colors [data-lesson-color="gray"], .student-colors [data-student-color="gray"] { --choice-color: #8b929d; }
.lesson-menu-divider { height: 1px; margin: 12px -2px 7px; background: #eceef1; }
.lesson-menu-remove { width: 100%; min-height: 38px; padding: 0 9px; border: 0; border-radius: 8px; color: #b20710; background: transparent; font-size: .76rem; font-weight: 800; text-align: left; cursor: pointer; }
.lesson-menu-remove:hover { background: rgba(229, 9, 20, .07); }
.lesson-menu-remove i { width: 20px; margin-right: 4px; text-align: center; }

.tracker-toast { max-width: min(360px, calc(100vw - 30px)); padding: 12px 16px; position: fixed; z-index: 50; right: 25px; bottom: 25px; border-radius: 11px; color: #fff; background: #20242b; box-shadow: 0 15px 40px rgba(0, 0, 0, .22); font-size: .78rem; font-weight: 700; opacity: 0; transform: translateY(12px); pointer-events: none; transition: .2s ease; }
.tracker-toast.is-visible { opacity: 1; transform: translateY(0); }
.tracker-toast.is-error { background: var(--red-dark); }

@media (max-width: 1050px) {
    .tracker-main { padding-inline: 24px; }
    .tracker-board { overflow-x: auto; grid-template-columns: repeat(3, minmax(285px, 1fr)); padding-bottom: 12px; }
}

@media (max-width: 720px) {
    .tracker-sidebar { width: min(290px, 88vw); }
    .tracker-main { padding: 18px 15px 35px; }
    .tracker-toolbar { margin-bottom: 27px; }
    .students-view-header { align-items: flex-start; flex-direction: column; gap: 15px; }
    .tracker-toolbar-student { padding-left: 8px; gap: 7px; }
    .tracker-toolbar-student { flex: 1; }
    .tracker-toolbar-student > strong { max-width: 125px; font-size: .9rem; }
    .tracker-board-open .tracker-toolbar-wordmark { display: none; }
    .toolbar-student-code { margin-left: auto; }
    .toolbar-student-code > span:first-child { display: none; }
    .tracker-board-open .save-indicator { width: 30px; height: 30px; padding: 0; border-radius: 9px; justify-content: center; font-size: 0; }
    .students-header-actions { width: 100%; flex-wrap: wrap; justify-content: space-between; }
    .teacher-code-pill { order: -1; width: 100%; justify-content: space-between; }
    .teacher-code-tooltip { right: 0; left: 0; width: 100%; }
    .toolbar-student-code-tooltip { width: min(300px, calc(100vw - 30px)); left: auto; right: 0; }
    .student-gallery { padding: 20px 12px; gap: 22px 8px; }
    .student-tile { width: 105px; flex-basis: 105px; }
    .student-avatar { width: 78px; height: 78px; }
    .tracker-header { align-items: flex-start; flex-direction: column; }
    .tracker-board { min-height: 610px; grid-template-columns: repeat(3, minmax(275px, 82vw)); }
    .board-column { padding: 15px; }
    .lesson-list { min-height: 420px; }
    .tracker-toast { right: 15px; bottom: 15px; }
}

@media (max-width: 520px) {
    .tracker-login-page { padding: 16px; align-items: flex-start; overflow-y: auto; }
    .tracker-login-card { margin: auto 0; padding: 26px 22px 28px; border-radius: 20px; }
    .tracker-login-icon { width: 44px; height: 44px; flex-basis: 44px; }
    .tracker-wordmark em { display: block; margin: 4px 0 0; }
}

@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after { scroll-behavior: auto !important; animation-duration: .01ms !important; animation-iteration-count: 1 !important; transition-duration: .01ms !important; }
}