/* Base styles, themes, navigation, popups, forms and toasts. */
:root {
    --nav-height: 48px;
    --leftbar-width: 320px;
    --hour-height: 56px;
    --radius: 6px;
    font-size: 15px;

    /* light theme */
    color-scheme: light;
    --bg: #f4f5f7;
    --panel: #ffffff;
    --panel-2: #f3f5f8;
    --hover: #eef1f5;
    --hover-strong: #e5e9ef;
    --input-bg: #ffffff;
    --text: #1f2328;
    --muted: #5f6b7a;
    --border: #d9dde3;
    --border-light: #f0f2f5;
    --grid-line: #d9dde3;
    --grid-line-light: #eef0f3;
    --accent: #1f6feb;
    --accent-dark: #174ea6;
    --accent-ring: rgba(31, 111, 235, 0.35);
    --danger: #d80000;
    --danger-dark: #b00000;
    --toast-bg: #1f2328;
    --toast-text: #ffffff;
    --toast-error: #b3261e;
    --toast-success: #1b7f3b;
    --notice-bg: #fff7d6;
    --notice-border: #f0d76a;
    --overlay: rgba(20, 24, 30, 0.35);
    --shadow: 0 2px 10px rgba(0, 0, 0, 0.08);
    --entry-text: #111111;
}

:root[data-theme="dark"] {
    color-scheme: dark;
    --bg: #0f1115;
    --panel: #181b21;
    --panel-2: #1f232b;
    --hover: #262b34;
    --hover-strong: #2f3540;
    --input-bg: #12151a;
    --text: #e6e8ec;
    --muted: #9aa4b2;
    --border: #2e343e;
    --border-light: #232831;
    --grid-line: #2e343e;
    --grid-line-light: #1f242c;
    --accent: #4c8dff;
    --accent-dark: #2f6fe0;
    --accent-ring: rgba(76, 141, 255, 0.4);
    --danger: #e5484d;
    --danger-dark: #c93c41;
    --toast-bg: #e6e8ec;
    --toast-text: #15181d;
    --toast-error: #d9534f;
    --toast-success: #2e9e5b;
    --notice-bg: #3a3414;
    --notice-border: #6b5d1a;
    --overlay: rgba(0, 0, 0, 0.55);
    --shadow: 0 2px 12px rgba(0, 0, 0, 0.5);
}

* { box-sizing: border-box; }

html, body { margin: 0; padding: 0; }

body {
    font-family: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    color: var(--text);
    background: var(--bg);
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

a { color: var(--accent); }
button, input, select { font: inherit; }
.hidden, [hidden] { display: none !important; }
body.mode-view .edit-only { display: none !important; }

/* logo variants per theme */
:root[data-theme="dark"] .logo-light { display: none; }
:root:not([data-theme="dark"]) .logo-dark { display: none; }

/* ------------------------------------------------------------------ nav */
#nav-wrapper { position: sticky; top: 0; z-index: 50; }

#nav {
    height: var(--nav-height);
    background: var(--panel);
    border-bottom: 1px solid var(--border);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 12px;
}

.nav-group { display: flex; align-items: center; gap: 4px; min-width: 0; }
.nav-left { flex: 1 1 0; }
.nav-middle { flex: 0 0 auto; justify-content: center; }
.nav-right { flex: 1 1 0; justify-content: flex-end; }

.nav-item {
    display: flex;
    align-items: center;
    justify-content: center;
    height: var(--nav-height);
    padding: 0 4px;
    color: var(--text);
    text-decoration: none;
    border-radius: 4px;
}
a.nav-item:hover { background: var(--hover); }

.nav-item button, .nav-item a.icon-button {
    background: none;
    border: 0;
    cursor: pointer;
    width: 38px;
    height: 38px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 4px;
    color: var(--text);
    text-decoration: none;
}
.nav-item button:hover, .nav-item button.active, .nav-item a.icon-button:hover { background: var(--hover-strong); }
.nav-item button.active { color: var(--accent); }
.nav-item button:disabled { opacity: 0.4; cursor: default; }
.nav-item .icon { width: 20px; height: 20px; }
#toggle-leftbar .icon { transition: transform 0.2s; }
#toggle-leftbar.active .icon { transform: rotate(180deg); }
#new-timetable, #lock-link { width: 38px; height: 38px; padding: 0; margin-left: 2px; }
.nav-left img { height: 26px; display: block; }

.nav-title { gap: 10px; padding-right: 2px; }
.tt-name { font-weight: 600; max-width: 28vw; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.semester-badge {
    font-size: 0.78rem;
    color: var(--muted);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 2px 8px;
    white-space: nowrap;
}
.semester-badge:empty { display: none; }

.nav-loader {
    width: 18px;
    height: 18px;
    border: 3px solid var(--border);
    border-top-color: var(--accent);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }

/* --------------------------------------------------------------- popups */
#nav-popup-bg {
    position: fixed;
    inset: var(--nav-height) 0 0 0;
    background: var(--overlay);
    z-index: 40;
    display: none;
}
#nav-popup-bg.enabled { display: block; }

.nav-popup {
    position: absolute;
    top: var(--nav-height);
    left: 50%;
    transform: translateX(-50%);
    width: min(560px, calc(100vw - 24px));
    background: var(--panel);
    border: 1px solid var(--border);
    border-top: 0;
    border-radius: 0 0 var(--radius) var(--radius);
    box-shadow: var(--shadow);
    z-index: 45;
    max-height: calc(100vh - var(--nav-height) - 16px);
    overflow: auto;
}
#nav-popup-content { padding: 16px 20px 20px; }
.popup-section h2 { margin: 0 0 12px; font-size: 1.1rem; }

form label { display: block; font-size: 0.85rem; color: var(--muted); margin: 10px 0 4px; }
form input[type=text], form input[type=time], form input[type=search], form input[type=password], form select {
    width: 100%;
    padding: 7px 9px;
    border: 1px solid var(--border);
    border-radius: 4px;
    background: var(--input-bg);
    color: var(--text);
}
form input:focus, form select:focus, button:focus-visible {
    outline: 2px solid var(--accent-ring);
    border-color: var(--accent);
}
form input:user-invalid { border-color: var(--danger); }
input.time-24 { font-variant-numeric: tabular-nums; }

input[type=submit], button.button, a.button, .color-form-row button {
    display: inline-block;
    margin-top: 12px;
    padding: 8px 14px;
    border-radius: 4px;
    border: 1px solid var(--accent-dark);
    background: var(--accent);
    color: #fff;
    cursor: pointer;
    text-decoration: none;
    font-weight: 500;
    text-align: center;
}
input[type=submit]:hover, button.button:hover, a.button:hover, .color-form-row button:hover { background: var(--accent-dark); }
.form-last-button { width: 100%; }
.danger { background: var(--danger) !important; border-color: var(--danger-dark) !important; color: #fff !important; }
.danger:hover { background: var(--danger-dark) !important; }

.checkbox-row { display: flex; align-items: center; gap: 8px; margin-top: 10px; }
.checkbox-row input { width: 16px; height: 16px; }
.checkbox-row label { margin: 0; color: var(--text); font-size: 0.95rem; }
hr { border: 0; border-top: 1px solid var(--border); margin: 16px 0; }

.ce-time-inputs { display: flex; gap: 10px; }
.ce-time-input { flex: 1; min-width: 0; }

#ce-color-buttons, .change-color-colors, #color-select {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
    align-items: center;
    margin-top: 4px;
}
.ce-color-button, .change-color-colors .color, #color-select .color {
    width: 30px;
    height: 30px;
    border-radius: 5px;
    border: 2px solid rgba(0, 0, 0, 0.12);
    cursor: pointer;
}
.ce-color-button:hover, .change-color-colors .color:hover, #color-select .color:hover { border-color: rgba(0, 0, 0, 0.55); }
.ce-color-button.selected, .change-color-colors .color.selected { border-color: var(--text); box-shadow: 0 0 0 2px var(--panel) inset; }
#ce-color-input { width: 110px !important; font-family: ui-monospace, Consolas, monospace; margin-left: 6px; }

.color-form-row { display: flex; gap: 8px; align-items: center; margin-top: 8px; }
.color-form-row input[type=text] { flex: 1; font-family: ui-monospace, Consolas, monospace; }
.color-form-row input[type=submit], .color-form-row button { margin-top: 0; white-space: nowrap; }

.export-options { display: flex; gap: 10px; flex-wrap: wrap; }
.export-options .button { flex: 1; margin-top: 0; }
.link-row { display: flex; gap: 8px; align-items: center; margin: 4px 0 8px; }
.link-row code {
    flex: 1;
    display: block;
    padding: 6px 8px;
    background: var(--panel-2);
    border: 1px solid var(--border);
    border-radius: 4px;
    font-size: 0.8rem;
    overflow-wrap: anywhere;
}
.copy-link {
    background: none;
    border: 1px solid var(--border);
    border-radius: 4px;
    width: 34px;
    height: 34px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    flex: 0 0 auto;
    color: var(--text);
}
.copy-link:hover { background: var(--hover); }
#export p { margin: 8px 0 2px; }

.hint { color: var(--muted); font-size: 0.82rem; }
.hint:empty { display: none; }
.link-button {
    background: none;
    border: 0;
    color: var(--accent);
    cursor: pointer;
    padding: 4px 0;
    margin-top: 8px;
    text-decoration: underline;
}

.entry-details { font-size: 0.9rem; line-height: 1.45; margin-bottom: 6px; }
.entry-details .detail-row { display: flex; gap: 10px; }
.entry-details .detail-label { color: var(--muted); min-width: 84px; flex: 0 0 auto; }
.entry-details .detail-value { overflow-wrap: anywhere; }
.external-links { display: flex; gap: 12px; flex-wrap: wrap; margin: 6px 0 4px; font-size: 0.88rem; }
.external-links a { display: inline-flex; align-items: center; gap: 4px; }
.external-links:empty { display: none; }

/* --------------------------------------------------------------- toasts */
#toasts {
    position: fixed;
    right: 16px;
    bottom: 16px;
    display: flex;
    flex-direction: column;
    gap: 8px;
    z-index: 100;
    max-width: min(380px, calc(100vw - 32px));
}
.toast {
    background: var(--toast-bg);
    color: var(--toast-text);
    padding: 10px 14px;
    border-radius: 6px;
    box-shadow: var(--shadow);
    font-size: 0.9rem;
    opacity: 0;
    transform: translateY(8px);
    transition: opacity 0.2s, transform 0.2s;
}
.toast.show { opacity: 1; transform: none; }
.toast.error { background: var(--toast-error); color: #fff; }
.toast.success { background: var(--toast-success); color: #fff; }

/* ---------------------------------------------------------------- misc */
#legal { text-align: center; font-size: 0.78rem; color: var(--muted); padding: 8px 12px; }
#legal a { color: var(--muted); }

.notice {
    margin: 12px;
    padding: 12px 14px;
    background: var(--notice-bg);
    border: 1px solid var(--notice-border);
    border-radius: 6px;
    font-size: 0.9rem;
}

body.page { align-items: center; justify-content: center; padding: 24px; }
.page-card {
    background: var(--panel);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 28px 32px;
    max-width: 640px;
    width: 100%;
    box-shadow: var(--shadow);
    line-height: 1.5;
}
.page-card h1 { font-size: 1.4rem; margin: 12px 0; }
.page-card h2 { font-size: 1.05rem; margin: 18px 0 6px; }
.page-logo img { height: 28px; }
.page-links { display: flex; gap: 10px; flex-wrap: wrap; margin-top: 12px; }
.page-links .button { margin-top: 0; }
.unlock-form { max-width: 360px; }
.form-error { color: var(--danger); font-size: 0.9rem; margin: 8px 0 0; }