/* ===========================================================
   Devscool by Acoula — Designsystem
   Cream + Charcoal · Outfit · Light & Dark
   =========================================================== */

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

/* --- Light (default) --- */
:root {
  --bg: #F2EDE4;
  --surface: #F2EDE4;
  --surface-2: #E8E0D2;
  --surface-hover: rgba(10, 10, 10, 0.04);
  --text: #0A0A0A;
  --muted: #6B6560;
  --muted-2: #8A847E;
  --border: #C8C0B4;
  --border-strong: #B5AD9F;
  --accent: #0A0A0A;
  --accent-fg: #F2EDE4;
  --glow: rgba(10, 10, 10, 0.04);
  --shadow: 0 12px 32px -16px rgba(10, 10, 10, 0.12);
  --code-fg: #8B4513;
  --code-bg: #E8E0D2;
  --pre-bg: #ECE5D9;

  --ok: #16A34A;
  --warn: #B45309;
  --bad: #DC2626;

  --tag-html: #B8552E;
  --tag-css:  #2D5FA8;
  --tag-js:   #8C6F18;
  --tag-py:   #1F8B7E;
  --tag-cpp:  #5E3FA8;
  --tag-game: #5E3FA8;

  --radius-sm: 0.5rem;
  --radius-md: 0.75rem;
  --radius-lg: 1rem;
  --radius-xl: 1.5rem;
  --radius-2xl: 2rem;

  --ease: cubic-bezier(0.4, 0, 0.2, 1);
}

/* --- Dark --- */
[data-theme="dark"] {
  --bg: #0A0A0A;
  --surface: #121212;
  --surface-2: #1A1A1A;
  --surface-hover: rgba(242, 237, 228, 0.04);
  --text: #F2EDE4;
  --muted: #A09A93;
  --muted-2: #6B6560;
  --border: #2A2A2A;
  --border-strong: #3A3A3A;
  --accent: #F2EDE4;
  --accent-fg: #0A0A0A;
  --glow: rgba(242, 237, 228, 0.03);
  --shadow: 0 12px 32px -12px rgba(0, 0, 0, 0.5);
  --code-fg: #FFB38A;
  --code-bg: #1A1A1A;
  --pre-bg: #060606;

  --tag-html: #ff8466;
  --tag-css:  #66a5ff;
  --tag-js:   #ffd866;
  --tag-py:   #4ad3c8;
  --tag-cpp:  #c4a0ff;
  --tag-game: #a98fff;
}

/* ===== Base ===== */
html, body { height: 100%; }
body {
  font-family: "Outfit", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  letter-spacing: -0.005em;
  transition: background-color 0.3s var(--ease), color 0.3s var(--ease);
}

.boot { padding: 80px; text-align: center; color: var(--muted); }

a {
  color: var(--text);
  text-decoration: none;
  transition: opacity 0.2s var(--ease);
}
a:hover { opacity: 0.65; }

/* Subtle ambient glow (mode-aware) */
body::before,
body::after {
  content: "";
  position: fixed;
  width: 50vw; height: 50vw;
  background: radial-gradient(circle, var(--glow), transparent 70%);
  pointer-events: none;
  z-index: 0;
}
body::before { top: -20%; left: -10%; }
body::after  { bottom: -20%; right: -10%; }

/* ===== Layout ===== */
.layout {
  display: grid;
  grid-template-columns: 280px 1fr;
  min-height: 100vh;
  position: relative;
  z-index: 1;
}

.sidebar {
  background: color-mix(in srgb, var(--bg) 70%, transparent);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-right: 1px solid var(--border);
  padding: 28px 18px;
  position: sticky;
  top: 0;
  height: 100vh;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
}

.brand {
  font-size: 22px;
  font-weight: 700;
  letter-spacing: -0.025em;
  color: var(--text);
}
.brand-sub {
  font-size: 11px;
  color: var(--muted);
  margin-bottom: 28px;
  letter-spacing: 0.02em;
  font-weight: 400;
}

.nav-section {
  font-size: 10px;
  text-transform: uppercase;
  letter-spacing: 0.14em;
  color: var(--muted-2);
  padding: 18px 12px 8px;
  font-weight: 500;
}

.nav-item {
  display: flex; align-items: center; gap: 10px;
  padding: 9px 12px;
  border-radius: var(--radius-md);
  cursor: pointer;
  font-size: 14px;
  font-weight: 500;
  color: var(--muted);
  transition: all 0.2s var(--ease);
}
.nav-item:hover {
  background: var(--surface-hover);
  color: var(--text);
  opacity: 1;
}
.nav-item.active {
  background: var(--surface-hover);
  color: var(--text);
}

.user-box {
  margin-top: auto;
  padding-top: 18px;
  border-top: 1px solid var(--border);
  font-size: 13px;
}
.user-box .uname { font-weight: 600; letter-spacing: -0.01em; }
.user-box .urole {
  color: var(--muted);
  font-size: 10px;
  text-transform: uppercase;
  letter-spacing: 0.14em;
  margin-top: 2px;
  font-weight: 500;
}
.user-box .logout,
.user-box .theme-toggle {
  margin-top: 10px;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  cursor: pointer;
  color: var(--muted);
  font-size: 12px;
  padding: 4px 0;
  background: transparent;
  border: none;
  font-family: inherit;
}
.user-box .logout:hover,
.user-box .theme-toggle:hover { color: var(--text); opacity: 1; background: transparent; }

main {
  padding: 56px 64px;
  max-width: 1080px;
  width: 100%;
}

/* ===== Floating theme toggle (login page) ===== */
.theme-fab {
  position: fixed;
  top: 20px; right: 20px;
  z-index: 5;
  width: 40px; height: 40px;
  border-radius: 50%;
  background: var(--surface);
  border: 1px solid var(--border);
  display: grid; place-items: center;
  cursor: pointer;
  font-size: 16px;
  transition: all 0.2s var(--ease);
}
.theme-fab:hover { border-color: var(--border-strong); transform: scale(1.05); }

/* ===== Login ===== */
.login-wrap {
  min-height: 100vh;
  display: grid;
  place-items: center;
  padding: 20px;
  position: relative;
  overflow: hidden;
}
.login-wrap::before {
  content: "";
  position: absolute;
  top: 50%; left: 50%;
  width: 80vmin; height: 80vmin;
  transform: translate(-50%, -50%);
  background: radial-gradient(circle, var(--glow), transparent 60%);
  pointer-events: none;
}
.login-card {
  position: relative;
  background: color-mix(in srgb, var(--surface) 85%, transparent);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 1px solid var(--border);
  padding: 44px;
  border-radius: var(--radius-2xl);
  width: 100%; max-width: 400px;
  z-index: 1;
}
.login-card h1 {
  font-size: 36px;
  font-weight: 700;
  letter-spacing: -0.035em;
  margin-bottom: 4px;
  color: var(--text);
}
.login-card .lead {
  color: var(--muted);
  font-size: 13px;
  margin-bottom: 32px;
  letter-spacing: 0.02em;
  text-transform: uppercase;
  font-weight: 500;
}

/* ===== Forms ===== */
.field { margin-bottom: 16px; }
.field label {
  display: block;
  font-size: 12px;
  color: var(--text);
  margin-bottom: 6px;
  font-weight: 500;
}
input[type="text"], input[type="password"], input[type="number"],
input[type="file"],
select, textarea {
  width: 100%;
  background: var(--surface);
  border: 1px solid var(--border);
  color: var(--text);
  padding: 12px 14px;
  border-radius: var(--radius-md);
  font-family: inherit;
  font-size: 14px;
  transition: all 0.2s var(--ease);
}
input:focus, select:focus, textarea:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--surface-hover);
}
input::placeholder, textarea::placeholder { color: var(--muted-2); }
textarea {
  resize: vertical;
  min-height: 110px;
  font-family: "JetBrains Mono", "SF Mono", Consolas, monospace;
  font-size: 13px;
  line-height: 1.6;
}
input[type="file"] { padding: 10px 14px; font-size: 13px; cursor: pointer; }

.field-row { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }

/* ===== Buttons ===== */
button, .btn {
  font-family: inherit;
  font-size: 14px;
  font-weight: 500;
  padding: 10px 18px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border);
  background: transparent;
  color: var(--text);
  cursor: pointer;
  transition: all 0.2s var(--ease);
  display: inline-block;
  letter-spacing: -0.005em;
}
button:hover, .btn:hover { background: var(--surface-hover); border-color: var(--border-strong); }

button.primary, .btn.primary {
  background: var(--accent);
  border-color: var(--accent);
  color: var(--accent-fg);
  font-weight: 600;
}
button.primary:hover, .btn.primary:hover { opacity: 0.85; }

button.danger, .btn.danger {
  color: var(--bad);
  border-color: color-mix(in srgb, var(--bad) 35%, transparent);
}
button.danger:hover { background: var(--bad); color: white; border-color: var(--bad); }

button.ok, .btn.ok {
  color: var(--ok);
  border-color: color-mix(in srgb, var(--ok) 35%, transparent);
}
button.ok:hover { background: var(--ok); color: white; border-color: var(--ok); }

button.small { padding: 6px 12px; font-size: 12px; }

.btn-row { display: flex; gap: 10px; flex-wrap: wrap; margin-top: 8px; }

/* ===== Typography ===== */
h2 {
  font-size: 34px;
  font-weight: 700;
  letter-spacing: -0.03em;
  margin-bottom: 8px;
  line-height: 1.15;
}
h3 {
  font-size: 18px;
  font-weight: 600;
  letter-spacing: -0.015em;
  margin: 28px 0 12px;
}
p {
  margin-bottom: 12px;
  color: var(--muted);
}
.lesson-body p { color: var(--text); opacity: 0.85; }
.lesson-body ul, .lesson-body ol { margin: 0 0 14px 22px; color: var(--text); opacity: 0.85; }
.lesson-body li { margin-bottom: 6px; }

/* ===== Tags ===== */
.lesson-tag {
  display: inline-block;
  font-size: 10px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.14em;
  padding: 4px 11px;
  border-radius: 999px;
  margin-bottom: 14px;
  background: var(--surface-hover);
  color: var(--text);
}
.tag-html { background: color-mix(in srgb, var(--tag-html) 14%, transparent); color: var(--tag-html); }
.tag-css  { background: color-mix(in srgb, var(--tag-css) 14%, transparent);  color: var(--tag-css); }
.tag-js, .tag-javascript { background: color-mix(in srgb, var(--tag-js) 16%, transparent); color: var(--tag-js); }
.tag-py, .tag-python { background: color-mix(in srgb, var(--tag-py) 14%, transparent); color: var(--tag-py); }
.tag-cpp, .tag-c { background: color-mix(in srgb, var(--tag-cpp) 16%, transparent); color: var(--tag-cpp); }
.tag-game { background: color-mix(in srgb, var(--tag-game) 16%, transparent); color: var(--tag-game); }

/* ===== Code ===== */
code {
  font-family: "JetBrains Mono", "SF Mono", Consolas, monospace;
  background: var(--code-bg);
  padding: 2px 7px;
  border-radius: var(--radius-sm);
  font-size: 13px;
  color: var(--code-fg);
  letter-spacing: 0;
  font-weight: 500;
}
pre {
  background: var(--pre-bg);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 18px 20px;
  overflow-x: auto;
  margin: 14px 0 18px;
}
pre code {
  background: none;
  padding: 0;
  color: var(--text);
  font-size: 13px;
  line-height: 1.65;
  font-weight: 400;
}

.tip {
  background: var(--surface-hover);
  border: 1px solid var(--border);
  border-left: 3px solid var(--accent);
  padding: 14px 18px;
  border-radius: var(--radius-md);
  margin: 18px 0;
  font-size: 14px;
  color: var(--text);
}

/* ===== Cards & Grid ===== */
.grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 16px;
  margin: 24px 0;
}
.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-2xl);
  padding: 24px;
  transition: all 0.25s var(--ease);
  display: block;
  color: var(--text);
}
a.card { text-decoration: none; }
.card:hover {
  border-color: var(--border-strong);
  transform: translateY(-2px);
  box-shadow: var(--shadow);
  opacity: 1;
}
.card .icon { font-size: 30px; margin-bottom: 10px; }
.card .title {
  font-size: 17px;
  font-weight: 600;
  margin-bottom: 4px;
  letter-spacing: -0.01em;
}
.card .desc {
  font-size: 13px;
  color: var(--muted);
  margin-bottom: 14px;
  line-height: 1.55;
}
.card .meta { font-size: 12px; color: var(--muted); }

.progress-bar {
  height: 4px;
  background: var(--surface-2);
  border-radius: 999px;
  overflow: hidden;
  margin: 8px 0 6px;
}
.progress-bar > div {
  height: 100%;
  background: var(--accent);
  transition: width 0.4s var(--ease);
  border-radius: 999px;
}

/* ===== Lesson list ===== */
.lesson-list { list-style: none; padding: 0; }
.lesson-list .section-head {
  font-size: 10px;
  text-transform: uppercase;
  letter-spacing: 0.14em;
  color: var(--muted-2);
  margin: 24px 0 10px;
  padding-left: 4px;
  font-weight: 500;
}
.lesson-list .lesson-row {
  display: flex; align-items: center; gap: 14px;
  padding: 16px 20px;
  border-radius: var(--radius-lg);
  background: var(--surface);
  border: 1px solid var(--border);
  margin-bottom: 8px;
  cursor: pointer;
  color: var(--text);
  transition: all 0.2s var(--ease);
}
.lesson-list .lesson-row:hover {
  border-color: var(--border-strong);
  transform: translateX(2px);
  opacity: 1;
}
.lesson-list .lesson-row .num {
  width: 28px; height: 28px;
  border-radius: 50%;
  background: var(--surface-2);
  display: grid; place-items: center;
  font-size: 12px;
  font-weight: 600;
  flex-shrink: 0;
  border: 1px solid var(--border);
  color: var(--muted);
  transition: all 0.2s var(--ease);
}
.lesson-row.status-approved .num {
  background: var(--accent);
  border-color: var(--accent);
  color: var(--accent-fg);
}
.lesson-row.status-pending .num {
  background: color-mix(in srgb, var(--warn) 15%, transparent);
  border-color: var(--warn);
  color: var(--warn);
}
.lesson-row.status-needs_work .num {
  background: color-mix(in srgb, var(--bad) 12%, transparent);
  border-color: var(--bad);
  color: var(--bad);
}
.lesson-list .lesson-row .title {
  flex: 1;
  font-weight: 500;
  letter-spacing: -0.005em;
}
.lesson-list .lesson-row .status {
  font-size: 10px;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--muted);
  font-weight: 500;
}

/* ===== Challenge box ===== */
.challenge-box {
  margin-top: 44px;
  padding: 32px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-2xl);
  position: relative;
  overflow: hidden;
}
.challenge-box::before {
  content: "";
  position: absolute;
  top: -50%; right: -20%;
  width: 60%; height: 200%;
  background: radial-gradient(circle, var(--glow), transparent 60%);
  pointer-events: none;
}
.challenge-box > * { position: relative; }
.challenge-box h3 {
  margin-top: 0;
  display: flex; align-items: center; gap: 8px;
}

/* ===== Tables ===== */
table {
  width: 100%;
  border-collapse: separate;
  border-spacing: 0;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
}
th, td {
  text-align: left;
  padding: 14px 18px;
  border-bottom: 1px solid var(--border);
  font-size: 14px;
}
th {
  color: var(--muted);
  font-size: 10px;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  font-weight: 600;
  background: var(--surface-2);
}
tr:last-child td { border-bottom: none; }
tr:hover td { background: var(--surface-hover); }

/* ===== Badges ===== */
.badge {
  display: inline-block;
  padding: 3px 10px;
  border-radius: 999px;
  font-size: 10px;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  font-weight: 600;
}
.badge-pending { background: color-mix(in srgb, var(--warn) 14%, transparent); color: var(--warn); }
.badge-approved { background: color-mix(in srgb, var(--ok) 14%, transparent); color: var(--ok); }
.badge-needs_work { background: color-mix(in srgb, var(--bad) 12%, transparent); color: var(--bad); }
.badge-admin { background: var(--accent); color: var(--accent-fg); }
.badge-student { background: var(--surface-hover); color: var(--text); }

/* ===== Header bar ===== */
.page-head {
  display: flex; align-items: flex-start; justify-content: space-between;
  gap: 16px; margin-bottom: 28px;
}
a.back, .back {
  display: inline-block;
  color: var(--muted);
  font-size: 13px;
  margin-bottom: 14px;
  font-weight: 500;
}
a.back:hover, .back:hover { color: var(--text); opacity: 1; }

.tabs {
  display: flex;
  gap: 4px;
  margin-bottom: 28px;
  border-bottom: 1px solid var(--border);
}
.tabs a {
  padding: 12px 16px;
  cursor: pointer;
  font-size: 14px;
  color: var(--muted);
  border-bottom: 2px solid transparent;
  margin-bottom: -1px;
  font-weight: 500;
  transition: all 0.2s var(--ease);
}
.tabs a:hover { color: var(--text); opacity: 1; }
.tabs a.active { color: var(--text); border-bottom-color: var(--accent); }

/* ===== Toast / Errors ===== */
.error-msg {
  background: color-mix(in srgb, var(--bad) 8%, transparent);
  border: 1px solid color-mix(in srgb, var(--bad) 30%, transparent);
  color: var(--bad);
  padding: 12px 16px;
  border-radius: var(--radius-md);
  margin-bottom: 16px;
  font-size: 14px;
}
.success-msg {
  background: color-mix(in srgb, var(--ok) 8%, transparent);
  border: 1px solid color-mix(in srgb, var(--ok) 30%, transparent);
  color: var(--ok);
  padding: 12px 16px;
  border-radius: var(--radius-md);
  margin-bottom: 16px;
  font-size: 14px;
}

/* ===== Modal ===== */
.modal-bg {
  position: fixed; inset: 0;
  background: color-mix(in srgb, var(--bg) 60%, rgba(0,0,0,0.5));
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  display: grid; place-items: center;
  z-index: 100; padding: 20px;
  animation: fadeIn 0.2s var(--ease);
}
@keyframes fadeIn { from { opacity: 0 } to { opacity: 1 } }
.modal {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-2xl);
  padding: 36px;
  max-width: 560px; width: 100%;
  max-height: 90vh; overflow-y: auto;
  box-shadow: var(--shadow);
}
.modal h3 {
  margin-top: 0;
  font-size: 24px;
  letter-spacing: -0.025em;
  margin-bottom: 6px;
}

/* ===== Submission ===== */
.submission {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 20px;
  margin-bottom: 12px;
}
.submission .sub-head {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 12px;
  font-size: 12px;
}
.submission pre { max-height: 400px; overflow: auto; margin: 8px 0; }
.submission .feedback {
  margin-top: 12px;
  padding: 14px 18px;
  background: var(--surface-hover);
  border: 1px solid var(--border);
  border-left: 3px solid var(--accent);
  border-radius: var(--radius-md);
  font-size: 14px;
}
.file-list {
  display: flex; flex-wrap: wrap; gap: 8px;
  margin: 8px 0;
}
.file-list a {
  padding: 5px 12px;
  background: var(--surface-2);
  border: 1px solid var(--border);
  border-radius: 999px;
  font-size: 12px;
  color: var(--text);
}
.file-list a:hover { border-color: var(--border-strong); opacity: 1; }

/* ===== Scrollbar ===== */
::-webkit-scrollbar { width: 10px; height: 10px; }
::-webkit-scrollbar-track { background: var(--bg); }
::-webkit-scrollbar-thumb { background: var(--border); border-radius: 999px; }
::-webkit-scrollbar-thumb:hover { background: var(--border-strong); }

details summary { cursor: pointer; font-weight: 500; }
details summary:hover { color: var(--text); opacity: 1; }

hr { border: none; border-top: 1px solid var(--border); margin: 18px 0; }

/* ===== Mobile ===== */
@media (max-width: 720px) {
  .layout { grid-template-columns: 1fr; }
  .sidebar { position: static; height: auto; padding: 20px; }
  main { padding: 32px 22px; }
  .field-row { grid-template-columns: 1fr; }
  .login-card { padding: 32px 24px; }
  h2 { font-size: 26px; }
  .theme-fab { top: 14px; right: 14px; }
}