/* ═══════════════════════════════════════════
   DERS ÖZETLERİ — Sade & Minimalist
   ═══════════════════════════════════════════ */

:root {
    --bg: #F7F7F7;
    --bg-elevated: #FFFFFF;
    --bg-subtle: #F0F0F0;
    --text: #0A0A0A;
    --text-secondary: #555555;
    --text-tertiary: #999999;
    --border: #E5E5E5;
    --border-strong: #D0D0D0;
    --accent: #0A0A0A;
    --accent-inverse: #FFFFFF;
    --accent-blue: #2196F3;
    --shadow: 0 4px 20px rgba(0,0,0,.06);
}

@media (prefers-color-scheme: dark) {
    :root {
        --bg: #0A0A0A;
        --bg-elevated: #1A1A1A;
        --bg-subtle: #141414;
        --text: #FFFFFF;
        --text-secondary: #B0B0B0;
        --text-tertiary: #707070;
        --border: #2A2A2A;
        --border-strong: #3A3A3A;
        --accent: #FFFFFF;
        --accent-inverse: #0A0A0A;
        --shadow: 0 4px 20px rgba(0,0,0,.4);
    }
}
html[data-theme="light"] {
    --bg: #F7F7F7; --bg-elevated: #FFFFFF; --bg-subtle: #F0F0F0;
    --text: #0A0A0A; --text-secondary: #555555; --text-tertiary: #999999;
    --border: #E5E5E5; --border-strong: #D0D0D0;
    --accent: #0A0A0A; --accent-inverse: #FFFFFF;
    --shadow: 0 4px 20px rgba(0,0,0,.06);
}
html[data-theme="dark"] {
    --bg: #0A0A0A; --bg-elevated: #1A1A1A; --bg-subtle: #141414;
    --text: #FFFFFF; --text-secondary: #B0B0B0; --text-tertiary: #707070;
    --border: #2A2A2A; --border-strong: #3A3A3A;
    --accent: #FFFFFF; --accent-inverse: #0A0A0A;
    --shadow: 0 4px 20px rgba(0,0,0,.4);
}

* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto,
                 'Helvetica Neue', Arial, sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.6;
    transition: background-color .3s ease, color .3s ease;
    -webkit-font-smoothing: antialiased;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.main-content { flex: 1; padding-bottom: 40px; }

.container {
    max-width: 900px;
    margin: 0 auto;
    padding: 0 16px;
}

/* ═══════════════ NAVBAR ═══════════════ */
.navbar {
    position: sticky;
    top: 0;
    z-index: 100;
    background: color-mix(in srgb, var(--bg) 85%, transparent);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border);
    padding: 12px 16px;
}
.nav-inner {
    max-width: 900px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 12px;
}
.nav-left { display: flex; align-items: center; gap: 8px; flex: 1; min-width: 0; }
.logo {
    font-size: 18px;
    font-weight: 800;
    color: var(--text);
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: 8px;
    letter-spacing: -0.5px;
}
.nav-actions { display: flex; gap: 6px; }
.nav-icon {
    background: var(--bg-elevated);
    border: 1px solid var(--border);
    color: var(--text);
    width: 40px;
    height: 40px;
    border-radius: 10px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 18px;
    text-decoration: none;
    transition: all .2s;
}
.nav-icon:hover { border-color: var(--border-strong); transform: scale(1.05); }

/* ═══════════════ SAYFA BAŞLIĞI ═══════════════ */
.page-header {
    max-width: 900px;
    margin: 0 auto;
    padding: 24px 16px 16px;
}
.page-header h1 {
    font-size: 24px;
    font-weight: 800;
    letter-spacing: -0.5px;
    line-height: 1.2;
    margin-bottom: 4px;
}
.page-header p {
    color: var(--text-secondary);
    font-size: 14px;
}

/* ═══════════════ SEARCH ═══════════════ */
.search-wrap {
    max-width: 900px;
    margin: 0 auto 12px;
    padding: 0 16px;
}
.search-input {
    width: 100%;
    padding: 14px 16px 14px 44px;
    background: var(--bg-elevated);
    border: 1px solid var(--border);
    border-radius: 12px;
    color: var(--text);
    font-size: 15px;
    font-family: inherit;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='20' height='20' viewBox='0 0 24 24' fill='none' stroke='%23999' stroke-width='2'%3E%3Ccircle cx='11' cy='11' r='8'/%3E%3Cpath d='m21 21-4.35-4.35'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: 14px center;
    transition: border-color .2s;
}
.search-input:focus { outline: none; border-color: var(--text); }

/* ═══════════════ KARTLAR ═══════════════ */
.card-list {
    max-width: 900px;
    margin: 0 auto;
    padding: 0 16px;
    display: flex;
    flex-direction: column;
    gap: 8px;
}
.card {
    background: var(--bg-elevated);
    border: 1px solid var(--border);
    border-radius: 14px;
    padding: 14px;
    text-decoration: none;
    color: var(--text);
    display: flex;
    align-items: center;
    gap: 12px;
    transition: all .2s;
}
.card:hover {
    border-color: var(--border-strong);
    transform: translateY(-1px);
    box-shadow: var(--shadow);
}
.card-icon {
    width: 44px;
    height: 44px;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 22px;
    flex-shrink: 0;
    background: var(--bg-subtle);
}
.card-body { flex: 1; min-width: 0; }
.card-title {
    font-size: 15px;
    font-weight: 600;
    color: var(--text);
    margin-bottom: 2px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}
.card-desc {
    font-size: 12px;
    color: var(--text-secondary);
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}
.card-arrow {
    font-size: 18px;
    color: var(--text-tertiary);
    flex-shrink: 0;
}

/* ═══════════════ ÖZET SAYFASI ═══════════════ */
.summary-wrap {
    max-width: 900px;
    margin: 0 auto;
    padding: 16px;
}
.summary-title {
    font-size: 24px;
    font-weight: 800;
    letter-spacing: -0.5px;
    line-height: 1.25;
    margin-bottom: 6px;
}
.summary-breadcrumb {
    font-size: 12px;
    color: var(--text-tertiary);
    margin-bottom: 20px;
}
.summary-breadcrumb a {
    color: var(--text-secondary);
    text-decoration: none;
}
.summary-breadcrumb a:hover { color: var(--text); }

/* İçerik blokları */
.content-block { margin-bottom: 16px; line-height: 1.7; }
.content-block h1, .content-block h2, .content-block h3, .content-block h4 {
    margin: 16px 0 8px;
    font-weight: 700;
    letter-spacing: -0.3px;
}
.content-block h1 { font-size: 22px; }
.content-block h2 { font-size: 19px; }
.content-block h3 { font-size: 17px; }
.content-block h4 { font-size: 15px; }
.content-block p { margin: 8px 0; font-size: 15px; }
.content-block ul, .content-block ol {
    margin: 8px 0;
    padding-left: 22px;
}
.content-block li { margin: 4px 0; font-size: 15px; }
.content-block a {
    color: var(--accent-blue);
    text-decoration: underline;
    text-underline-offset: 2px;
}
.content-block img {
    max-width: 100%;
    height: auto;
    border-radius: 12px;
    margin: 12px 0;
}
.content-block blockquote {
    padding: 12px 16px;
    margin: 12px 0;
    background: var(--bg-subtle);
    border-left: 3px solid var(--accent-blue);
    border-radius: 8px;
    color: var(--text-secondary);
    font-style: italic;
}
.content-block code {
    background: var(--bg-subtle);
    padding: 2px 6px;
    border-radius: 4px;
    font-family: monospace;
    font-size: 13px;
}
.content-block pre {
    background: #1A1A1A;
    color: #FFF;
    padding: 14px;
    border-radius: 10px;
    overflow-x: auto;
    margin: 12px 0;
}
.content-block table {
    width: 100%;
    border-collapse: collapse;
    margin: 12px 0;
    font-size: 14px;
}
.content-block th, .content-block td {
    padding: 8px 12px;
    border: 1px solid var(--border);
    text-align: left;
}
.content-block th { background: var(--bg-subtle); font-weight: 700; }

/* Özel kutular */
.block-important {
    background: rgba(255, 152, 0, .08);
    border: 1px solid rgba(255, 152, 0, .3);
    border-radius: 12px;
    padding: 16px;
    margin: 12px 0;
}
.block-important::before {
    content: '⚠️ Önemli Bilgi';
    display: block;
    font-weight: 700;
    color: #FF9800;
    font-size: 13px;
    margin-bottom: 8px;
}
.block-example {
    background: rgba(33, 150, 243, .08);
    border: 1px solid rgba(33, 150, 243, .3);
    border-radius: 12px;
    padding: 16px;
    margin: 12px 0;
}
.block-example::before {
    content: '📌 Örnek';
    display: block;
    font-weight: 700;
    color: #2196F3;
    font-size: 13px;
    margin-bottom: 8px;
}

/* Video */
.video-container {
    position: relative;
    padding-bottom: 56.25%;
    height: 0;
    overflow: hidden;
    border-radius: 12px;
    margin: 12px 0;
    background: #000;
}
.video-container iframe,
.video-container video {
    position: absolute;
    top: 0; left: 0;
    width: 100%;
    height: 100%;
    border: none;
}

/* ═══════════════ ARAMA ═══════════════ */
.search-result {
    display: block;
    padding: 14px;
    background: var(--bg-elevated);
    border: 1px solid var(--border);
    border-radius: 12px;
    text-decoration: none;
    color: var(--text);
    margin-bottom: 8px;
}
.search-result:hover {
    border-color: var(--border-strong);
}
.search-result-title {
    font-size: 15px;
    font-weight: 600;
    margin-bottom: 2px;
}
.search-result-path {
    font-size: 12px;
    color: var(--text-secondary);
}

/* ═══════════════ EMPTY STATE ═══════════════ */
.empty {
    text-align: center;
    padding: 60px 20px;
    color: var(--text-secondary);
}
.empty-icon {
    font-size: 56px;
    margin-bottom: 12px;
}
.empty-title {
    font-size: 17px;
    font-weight: 700;
    color: var(--text);
    margin-bottom: 4px;
}
.empty-text {
    font-size: 14px;
}

/* ═══════════════ FOOTER ═══════════════ */
.footer {
    border-top: 1px solid var(--border);
    padding: 40px 16px 24px;
    margin-top: 40px;
}
.footer-inner {
    max-width: 900px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: 2fr 1fr 1fr;
    gap: 32px;
    margin-bottom: 24px;
}
.footer-brand h3 {
    font-size: 17px;
    font-weight: 800;
    margin-bottom: 8px;
}
.footer-brand p {
    color: var(--text-secondary);
    font-size: 13px;
    max-width: 320px;
}
.footer-col h4 {
    font-size: 12px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 1px;
    color: var(--text-tertiary);
    margin-bottom: 12px;
}
.footer-col a {
    display: block;
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 14px;
    padding: 3px 0;
    transition: color .2s;
}
.footer-col a:hover { color: var(--text); }
.footer-bottom {
    max-width: 900px;
    margin: 0 auto;
    padding-top: 20px;
    border-top: 1px solid var(--border);
    text-align: center;
    color: var(--text-tertiary);
    font-size: 12px;
}

/* ═══════════════ MOBILE ═══════════════ */
@media (max-width: 768px) {
    .footer-inner { grid-template-columns: 1fr; gap: 24px; }
    .page-header h1 { font-size: 20px; }
    .summary-title { font-size: 20px; }
    .content-block h1 { font-size: 20px; }
    .content-block h2 { font-size: 17px; }
    .content-block h3 { font-size: 15px; }
}