:root {
    --stone-050: #fafaf9;
    --stone-100: #f5f5f4;
    --stone-200: #e7e5e4;
    --stone-300: #d6d3d1;
    --stone-400: #a8a29e;
    --stone-500: #78716c;
    --stone-600: #57534e;
    --stone-700: #44403c;
    --stone-800: #292524;
    --stone-900: #1c1917;
    --stone-950: #0c0a09;

    --blue: #3b82f6;
    --red: #ef4444;
    --green: #22c55e;
    --amber: #f59e0b;

    --bg: var(--stone-950);
    --bg-raised: var(--stone-900);
    --bg-surface: var(--stone-800);
    --border: var(--stone-800);
    --border-strong: var(--stone-600);
    --text: var(--stone-200);
    --text-muted: var(--stone-400);
    --text-faint: var(--stone-500);
    --text-bright: var(--stone-100);
    --accent: var(--blue);
    --accent-hover: #5193f8;

    --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    --font-mono: "JetBrains Mono", "SF Mono", "Fira Code", "Roboto Mono", "Cascadia Code", monospace;
    --line-height: 1.6;
    --line-height-tight: 1.2;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    border-radius: 0 !important;
}

body {
    background-color: var(--bg);
    color: var(--text);
    font-family: var(--font-sans);
    line-height: var(--line-height);
    min-height: 100vh;
}

h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-mono);
    font-weight: 600;
    line-height: var(--line-height-tight);
    color: var(--text-bright);
}

a {
    color: var(--accent);
    text-decoration: none;
    transition: color 0.15s;
}

a:hover {
    color: var(--accent-hover);
}

code, pre {
    font-family: var(--font-mono);
    font-size: 0.875rem;
}

button {
    cursor: pointer;
    font-family: var(--font-mono);
    font-size: 0.875rem;
    font-weight: 600;
    transition: background-color 0.15s, border-color 0.15s, color 0.15s;
}

input, select, textarea {
    font-family: var(--font-sans);
    font-size: 0.875rem;
    transition: border-color 0.15s;
}

.nav {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 24px;
    height: 52px;
    background-color: var(--bg-raised);
    border-bottom: 1px solid var(--border);
    position: sticky;
    top: 0;
    z-index: 100;
}

.nav-brand {
    font-family: var(--font-mono);
    font-size: 1rem;
    font-weight: 700;
    color: var(--text-bright);
    letter-spacing: -0.02em;
    text-decoration: none;
}

.nav-brand:hover {
    color: var(--text-bright);
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 0;
    list-style: none;
}

.nav-links a {
    display: block;
    padding: 6px 14px;
    color: var(--text-muted);
    font-family: var(--font-mono);
    font-size: 0.8rem;
    font-weight: 500;
    border: 1px solid transparent;
    transition: color 0.15s, border-color 0.15s, background-color 0.15s;
}

.nav-links a:hover {
    color: var(--text);
    border-color: var(--border);
    background-color: var(--bg-surface);
}

.nav-links a.active {
    color: var(--text-bright);
    border-color: var(--border-strong);
    background-color: var(--bg-surface);
}

.nav-right {
    display: flex;
    align-items: center;
    gap: 12px;
}

.nav-user {
    font-family: var(--font-mono);
    font-size: 0.75rem;
    color: var(--text-faint);
}

.main {
    max-width: 1280px;
    margin: 0 auto;
    padding: 32px 24px;
}

.page-header {
    margin-bottom: 32px;
    padding-bottom: 16px;
    border-bottom: 1px solid var(--border);
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    gap: 16px;
    flex-wrap: wrap;
}

.page-header h1 {
    font-size: 1.5rem;
    letter-spacing: -0.03em;
}

.page-header .subtitle {
    font-family: var(--font-mono);
    font-size: 0.75rem;
    color: var(--text-faint);
    margin-top: 4px;
}

.page-actions {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
    align-items: center;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 7px 14px;
    font-family: var(--font-mono);
    font-size: 0.8rem;
    font-weight: 600;
    border: 1px solid var(--border-strong);
    background: transparent;
    color: var(--text-muted);
    cursor: pointer;
    transition: background-color 0.15s, color 0.15s, border-color 0.15s;
}

.btn:hover {
    background-color: var(--bg-surface);
    color: var(--text);
    border-color: var(--border-strong);
}

.btn-primary {
    background-color: var(--accent);
    border-color: var(--accent);
    color: #fff;
}

.btn-primary:hover {
    background-color: var(--accent-hover);
    border-color: var(--accent-hover);
    color: #fff;
}

.btn-sm {
    padding: 4px 10px;
    font-size: 0.73rem;
}

.btn-ghost {
    border-color: transparent;
    background: transparent;
    color: var(--text-muted);
}

.btn-ghost:hover {
    border-color: var(--border);
    background-color: var(--bg-raised);
    color: var(--text);
}

.select-input {
    background-color: var(--bg-raised);
    border: 1px solid var(--border-strong);
    color: var(--text);
    padding: 6px 10px;
    font-family: var(--font-mono);
    font-size: 0.8rem;
    cursor: pointer;
    appearance: none;
    padding-right: 28px;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath fill='%2378716c' d='M6 8L1 3h10z'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 8px center;
}

.select-input:focus {
    outline: none;
    border-color: var(--accent);
}

.card {
    background-color: var(--bg-raised);
    border: 1px solid var(--border);
    padding: 20px;
}

.card + .card {
    margin-top: 16px;
}

.card-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 16px;
}

.card-title {
    font-family: var(--font-mono);
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--text-bright);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.stat-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
    gap: 12px;
    margin-bottom: 32px;
}

.stat-card {
    background-color: var(--bg-raised);
    border: 1px solid var(--border);
    padding: 16px 20px;
}

.stat-label {
    font-family: var(--font-mono);
    font-size: 0.7rem;
    color: var(--text-faint);
    text-transform: uppercase;
    letter-spacing: 0.08em;
    margin-bottom: 6px;
}

.stat-value {
    font-family: var(--font-mono);
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--text-bright);
    letter-spacing: -0.03em;
    line-height: 1;
}

.stat-sub {
    font-family: var(--font-mono);
    font-size: 0.7rem;
    color: var(--text-muted);
    margin-top: 4px;
}

.stat-value.good { color: var(--green); }
.stat-value.avg { color: var(--amber); }
.stat-value.bad { color: var(--red); }

.grade-badge {
    display: inline-block;
    font-family: var(--font-mono);
    font-size: 0.75rem;
    font-weight: 700;
    padding: 2px 7px;
    border: 1px solid currentColor;
}

.grade-badge.good { color: var(--green); }
.grade-badge.avg { color: var(--amber); }
.grade-badge.bad { color: var(--red); }
.grade-badge.special { color: var(--text-faint); border-color: var(--border); }

.chart-container {
    background-color: var(--bg-raised);
    border: 1px solid var(--border);
    padding: 20px;
    margin-bottom: 24px;
}

.chart-title {
    font-family: var(--font-mono);
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--text-faint);
    text-transform: uppercase;
    letter-spacing: 0.08em;
    margin-bottom: 16px;
}

.chart-wrap {
    position: relative;
}

.grades-table-wrap {
    overflow-x: auto;
    margin-bottom: 32px;
}

.grades-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.8rem;
}

.grades-table th {
    font-family: var(--font-mono);
    font-size: 0.7rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.06em;
    color: var(--text-faint);
    padding: 8px 12px;
    text-align: left;
    border-bottom: 1px solid var(--border);
    white-space: nowrap;
}

.grades-table td {
    padding: 9px 12px;
    border-bottom: 1px solid var(--border);
    color: var(--text);
    vertical-align: middle;
}

.grades-table tbody tr:hover {
    background-color: var(--bg-raised);
}

.grades-table tbody tr.has-best {
    background-color: rgba(34, 197, 94, 0.06);
}

.subject-tag {
    display: inline-block;
    font-family: var(--font-mono);
    font-size: 0.7rem;
    padding: 2px 7px;
    border-left: 3px solid var(--subject-color, var(--accent));
    background-color: var(--bg-surface);
    color: var(--text);
    max-width: 200px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.trophy {
    display: inline-block;
    margin-left: 6px;
    font-size: 0.75rem;
    vertical-align: middle;
}

.schedule-wrap {
    overflow-x: auto;
    margin-bottom: 32px;
}

.schedule-grid {
    display: grid;
    grid-template-columns: 52px repeat(5, 1fr);
    min-width: 700px;
    border: 1px solid var(--border);
}

.schedule-day-header {
    font-family: var(--font-mono);
    font-size: 0.7rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.06em;
    color: var(--text-faint);
    padding: 8px;
    border-bottom: 1px solid var(--border);
    border-right: 1px solid var(--border);
    background-color: var(--bg-raised);
    text-align: center;
}

.schedule-time-col {
    font-family: var(--font-mono);
    font-size: 0.65rem;
    color: var(--text-faint);
    padding: 0 6px;
    text-align: right;
    user-select: none;
}

.schedule-body {
    display: contents;
}

.schedule-day-col {
    border-right: 1px solid var(--border);
    position: relative;
    min-height: 600px;
}

.schedule-day-col:last-child {
    border-right: none;
}

.lesson-block {
    position: absolute;
    left: 2px;
    right: 2px;
    padding: 4px 6px;
    overflow: hidden;
    border-left: 3px solid var(--subject-color, var(--accent));
    background-color: var(--bg-surface);
    border-top: 1px solid var(--border);
    border-bottom: 1px solid var(--border);
    border-right: 1px solid var(--border);
    cursor: default;
    transition: background-color 0.15s;
    min-height: 28px;
}

.lesson-block:hover {
    background-color: var(--bg-raised);
    z-index: 2;
}

.lesson-block.cancelled {
    opacity: 0.5;
    text-decoration: line-through;
    border-left-color: var(--red);
}

.lesson-subject {
    font-family: var(--font-mono);
    font-size: 0.7rem;
    font-weight: 600;
    color: var(--text-bright);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.lesson-meta {
    font-size: 0.63rem;
    color: var(--text-muted);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.lesson-status {
    font-size: 0.63rem;
    color: var(--amber);
    font-style: italic;
    white-space: nowrap;
}

.time-slot-line {
    position: absolute;
    left: 0;
    right: 0;
    height: 1px;
    background-color: var(--border);
    pointer-events: none;
}

.time-slot-line.hour {
    background-color: var(--stone-700);
}

.assignment-list {
    display: flex;
    flex-direction: column;
    gap: 0;
}

.assignment-item {
    display: grid;
    grid-template-columns: 3px 1fr auto;
    border: 1px solid var(--border);
    border-top: none;
    background-color: var(--bg-raised);
    transition: background-color 0.15s;
}

.assignment-item:first-child {
    border-top: 1px solid var(--border);
}

.assignment-item:hover {
    background-color: var(--bg-surface);
}

.assignment-item.done {
    opacity: 0.45;
}

.assignment-stripe {
    background-color: var(--subject-color, var(--stone-600));
}

.assignment-body {
    padding: 12px 16px;
}

.assignment-subject {
    font-family: var(--font-mono);
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--text-bright);
    margin-bottom: 3px;
}

.assignment-desc {
    font-size: 0.82rem;
    color: var(--text);
    margin-bottom: 8px;
    line-height: 1.45;
}

.assignment-meta {
    display: flex;
    gap: 12px;
    align-items: center;
    flex-wrap: wrap;
}

.assignment-deadline {
    font-family: var(--font-mono);
    font-size: 0.7rem;
    color: var(--text-faint);
}

.assignment-deadline.overdue {
    color: var(--red);
}

.assignment-deadline.soon {
    color: var(--amber);
}

.assignment-return {
    font-family: var(--font-mono);
    font-size: 0.68rem;
    color: var(--text-faint);
    background-color: var(--bg-surface);
    padding: 2px 6px;
    border: 1px solid var(--border);
}

.assignment-attachments {
    font-family: var(--font-mono);
    font-size: 0.68rem;
    color: var(--accent);
}

.assignment-right {
    padding: 12px;
    display: flex;
    align-items: center;
}

.login-wrap {
    display: flex;
    min-height: 100vh;
    align-items: center;
    justify-content: center;
    padding: 24px;
}

.login-box {
    width: 100%;
    max-width: 420px;
    border: 1px solid var(--border);
    background-color: var(--bg-raised);
}

.login-header {
    padding: 24px 28px 20px;
    border-bottom: 1px solid var(--border);
}

.login-title {
    font-size: 1.25rem;
    letter-spacing: -0.03em;
}

.login-subtitle {
    font-family: var(--font-mono);
    font-size: 0.72rem;
    color: var(--text-faint);
    margin-top: 4px;
}

.login-form {
    padding: 24px 28px;
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.field {
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.field label {
    font-family: var(--font-mono);
    font-size: 0.72rem;
    font-weight: 600;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.06em;
}

.field input {
    background-color: var(--bg);
    border: 1px solid var(--border-strong);
    color: var(--text);
    padding: 9px 12px;
    font-family: var(--font-sans);
    font-size: 0.875rem;
    width: 100%;
    outline: none;
    transition: border-color 0.15s;
}

.field input:focus {
    border-color: var(--accent);
}

.field input::placeholder {
    color: var(--stone-600);
}

.login-error {
    background-color: rgba(239, 68, 68, 0.1);
    border: 1px solid rgba(239, 68, 68, 0.4);
    color: var(--red);
    padding: 10px 14px;
    font-family: var(--font-mono);
    font-size: 0.78rem;
    display: none;
}

.login-error.visible {
    display: block;
}

.loading-overlay {
    display: none;
    position: fixed;
    inset: 0;
    background-color: rgba(12, 10, 9, 0.8);
    z-index: 9999;
    align-items: center;
    justify-content: center;
    flex-direction: column;
    gap: 16px;
}

.loading-overlay.visible {
    display: flex;
}

.spinner {
    width: 32px;
    height: 32px;
    border: 2px solid var(--border);
    border-top-color: var(--accent);
    animation: spin 0.65s linear infinite;
}

.loading-text {
    font-family: var(--font-mono);
    font-size: 0.8rem;
    color: var(--text-faint);
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

.empty-state {
    text-align: center;
    padding: 64px 24px;
    color: var(--text-faint);
    font-family: var(--font-mono);
    font-size: 0.85rem;
}

.empty-state .icon {
    font-size: 2rem;
    margin-bottom: 12px;
    opacity: 0.5;
}

.error-banner {
    background-color: rgba(239, 68, 68, 0.08);
    border: 1px solid rgba(239, 68, 68, 0.3);
    color: var(--red);
    padding: 12px 16px;
    font-family: var(--font-mono);
    font-size: 0.8rem;
    margin-bottom: 24px;
    display: none;
}

.error-banner.visible {
    display: block;
}

.period-selector {
    display: flex;
    align-items: center;
    gap: 8px;
}

.period-selector label {
    font-family: var(--font-mono);
    font-size: 0.72rem;
    color: var(--text-faint);
    text-transform: uppercase;
    letter-spacing: 0.06em;
}

.week-nav {
    display: flex;
    align-items: center;
    gap: 8px;
}

.week-label {
    font-family: var(--font-mono);
    font-size: 0.8rem;
    color: var(--text-muted);
    min-width: 80px;
    text-align: center;
}

.subjects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 12px;
    margin-bottom: 32px;
}

.subject-card {
    background-color: var(--bg-raised);
    border: 1px solid var(--border);
    border-left: 4px solid var(--subject-color, var(--accent));
    padding: 16px;
    cursor: pointer;
    transition: background-color 0.15s, border-left-color 0.15s;
}

.subject-card:hover {
    background-color: var(--bg-surface);
}

.subject-card.active {
    border-left-color: var(--accent);
    background-color: var(--bg-surface);
}

.subject-card-name {
    font-family: var(--font-mono);
    font-size: 0.82rem;
    font-weight: 600;
    color: var(--text-bright);
    margin-bottom: 8px;
}

.subject-card-stats {
    display: grid;
    grid-template-columns: 1fr 1fr 1fr;
    gap: 8px;
}

.subject-card-stat {
    text-align: center;
}

.subject-card-stat .val {
    font-family: var(--font-mono);
    font-size: 1.1rem;
    font-weight: 700;
    line-height: 1;
}

.subject-card-stat .lbl {
    font-size: 0.65rem;
    color: var(--text-faint);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.tab-bar {
    display: flex;
    border-bottom: 1px solid var(--border);
    margin-bottom: 24px;
}

.tab-item {
    font-family: var(--font-mono);
    font-size: 0.78rem;
    font-weight: 600;
    padding: 10px 18px;
    color: var(--text-muted);
    cursor: pointer;
    border-bottom: 2px solid transparent;
    transition: color 0.15s, border-color 0.15s;
    background: none;
    border-top: none;
    border-left: none;
    border-right: none;
}

.tab-item:hover {
    color: var(--text);
}

.tab-item.active {
    color: var(--text-bright);
    border-bottom-color: var(--accent);
}

.panel {
    display: none;
}

.panel.active {
    display: block;
}

.export-menu {
    position: relative;
}

.export-dropdown {
    display: none;
    position: absolute;
    right: 0;
    top: calc(100% + 4px);
    background-color: var(--bg-raised);
    border: 1px solid var(--border-strong);
    min-width: 180px;
    z-index: 50;
    box-shadow: 0 8px 24px rgba(0,0,0,0.5);
}

.export-dropdown.open {
    display: block;
}

.export-option {
    display: block;
    width: 100%;
    padding: 10px 16px;
    text-align: left;
    font-family: var(--font-mono);
    font-size: 0.78rem;
    color: var(--text-muted);
    background: none;
    border: none;
    cursor: pointer;
    border-bottom: 1px solid var(--border);
    transition: background-color 0.15s, color 0.15s;
}

.export-option:last-child {
    border-bottom: none;
}

.export-option:hover {
    background-color: var(--bg-surface);
    color: var(--text-bright);
}

.export-option .format-tag {
    font-size: 0.65rem;
    color: var(--text-faint);
    margin-left: 8px;
}

.compare-bar {
    display: flex;
    align-items: center;
    gap: 8px;
    height: 20px;
}

.compare-bar-fill {
    height: 8px;
    background-color: var(--accent);
    transition: width 0.3s;
}

.compare-bar-fill.class {
    background-color: var(--stone-600);
}

.compare-bar-label {
    font-family: var(--font-mono);
    font-size: 0.7rem;
    color: var(--text-faint);
    min-width: 36px;
    text-align: right;
}

@media (max-width: 768px) {
    .stat-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .subjects-grid {
        grid-template-columns: 1fr;
    }

    .page-header {
        flex-direction: column;
        align-items: flex-start;
    }

    .main {
        padding: 20px 16px;
    }

    .nav {
        padding: 0 16px;
    }
}