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

body {
    font-family: 'Inter', system-ui, -apple-system, sans-serif;
    background: #0c0d12;
    color: #e4e6ed;
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    display: flex;
}

.sidebar {
    position: fixed;
    top: 0;
    left: 0;
    width: 280px;
    height: 100vh;
    background: #10111a;
    border-right: 1px solid #222436;
    padding: 24px 18px;
    overflow-y: auto;
    z-index: 100;
    transform: translateX(-100%);
    transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: 4px 0 24px rgba(0, 0, 0, 0.5);
}

.sidebar.open {
    transform: translateX(0);
}

.sidebar-toggle {
    position: fixed;
    top: 16px;
    left: 16px;
    z-index: 101;
    background: #181924;
    border: 1px solid #222436;
    border-radius: 10px;
    padding: 8px 12px;
    cursor: pointer;
    color: #8b8fa4;
    transition: 0.2s;
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 0.8rem;
    font-weight: 500;
}

.sidebar-toggle:hover {
    border-color: #4f7cff;
    color: #e4e6ed;
}

.sidebar-toggle.hidden {
    display: none;
}

.sidebar-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.6);
    z-index: 99;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.3s;
}

.sidebar-overlay.show {
    opacity: 1;
    pointer-events: auto;
}

.sidebar-header {
    display: flex;
    align-items: center;
    margin-bottom: 4px;
}

.sidebar-header h2 {
    font-size: 1rem;
    font-weight: 700;
    color: #e4e6ed;
    display: flex;
    align-items: center;
    gap: 10px;
}

.sidebar-close {
    background: none;
    border: none;
    color: #555871;
    cursor: pointer;
    margin-left: auto;
    padding: 4px;
}

.sidebar-close:hover {
    color: #e4e6ed;
}

.sidebar .sub {
    font-size: 0.7rem;
    color: #555871;
    margin-bottom: 20px;
    border-bottom: 1px solid #222436;
    padding-bottom: 12px;
}

.sidebar .section {
    margin-bottom: 20px;
}

.sidebar .section h4 {
    font-size: 0.7rem;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    color: #555871;
    margin-bottom: 6px;
    display: flex;
    align-items: center;
    gap: 6px;
}

.sidebar .section pre {
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.7rem;
    background: #0c0d12;
    padding: 10px 12px;
    border-radius: 8px;
    border: 1px solid #222436;
    color: #e4e6ed;
    overflow-x: auto;
    white-space: pre-wrap;
    word-break: break-word;
    line-height: 1.7;
}

.sidebar .section pre .kw {
    color: #c678dd;
}

.sidebar .section pre .str {
    color: #98c379;
}

.sidebar .section pre .cmt {
    color: #5c6370;
    font-style: italic;
}

.sidebar .section pre .type {
    color: #e5c07b;
}

.sidebar .section pre .fn {
    color: #61afef;
}

.sidebar .section pre .num {
    color: #d19a66;
}

.sidebar .section pre .ann {
    color: #56b6c2;
}

/* Main */
.page {
    max-width: 720px;
    margin: 0 auto;
    padding: 80px 18px 64px 18px;
    flex: 1;
}

/* Colors */
:root {
    --bg: #0c0d12;
    --bg2: #13141c;
    --bg3: #181924;
    --text: #e4e6ed;
    --text2: #8b8fa4;
    --text3: #555871;
    --accent: #4f7cff;
    --accent-dim: rgba(79, 124, 255, 0.12);
    --green: #34d399;
    --green-dim: rgba(52, 211, 153, 0.12);
    --border: #222436;
    --r: 12px;
    --mono: 'JetBrains Mono', 'Fira Code', monospace;
}

/* Head */
.header {
    text-align: center;
    margin-bottom: 36px;
}

.header h1 {
    font-size: 1.8rem;
    font-weight: 800;
    letter-spacing: -0.3px;
    margin-bottom: 6px;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    flex-wrap: wrap;
}

.header h1 .badge {
    font-size: 0.65rem;
    font-weight: 600;
    background: var(--accent-dim);
    color: var(--accent);
    padding: 2px 14px;
    border-radius: 20px;
    border: 1px solid rgba(79, 124, 255, 0.25);
    letter-spacing: 0.3px;
}

.header p {
    color: var(--text2);
    font-size: 0.95rem;
}

/* Step */
.step {
    position: relative;
    padding: 24px 0 20px 56px;
    opacity: 0;
    transform: translateY(18px);
    animation: fadeIn 0.5s forwards;
}

.step:nth-child(1) {
    animation-delay: 0.1s;
}

.step:nth-child(2) {
    animation-delay: 0.25s;
}

.step:nth-child(3) {
    animation-delay: 0.4s;
}

.step:nth-child(4) {
    animation-delay: 0.55s;
}

.step:nth-child(5) {
    animation-delay: 0.7s;
}

@keyframes fadeIn {
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.step-num {
    position: absolute;
    left: 0;
    top: 24px;
    width: 38px;
    height: 38px;
    border-radius: 50%;
    background: var(--accent-dim);
    color: var(--accent);
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 800;
    font-size: 0.95rem;
    border: 2px solid var(--accent);
}

.step.done .step-num {
    background: var(--green-dim);
    color: var(--green);
    border-color: var(--green);
}

.step h3 {
    font-size: 1.05rem;
    font-weight: 700;
    margin-bottom: 4px;
    display: flex;
    align-items: center;
    gap: 10px;
    flex-wrap: wrap;
}

.step h3 .tag {
    font-size: 0.6rem;
    font-weight: 600;
    background: var(--bg3);
    color: var(--text2);
    padding: 0 12px;
    border-radius: 12px;
    border: 1px solid var(--border);
    letter-spacing: 0.3px;
}

.step p {
    color: var(--text2);
    font-size: 0.9rem;
    margin-bottom: 14px;
}

.step p code {
    font-family: var(--mono);
    background: var(--bg2);
    padding: 1px 8px;
    border-radius: 6px;
    font-size: 0.8rem;
    color: var(--accent);
    border: 1px solid var(--border);
}

/* Code */
.code-block {
    background: var(--bg2);
    border: 1px solid var(--border);
    border-radius: var(--r);
    overflow: hidden;
    margin: 14px 0 18px;
}

.code-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 6px 14px;
    background: var(--bg3);
    border-bottom: 1px solid var(--border);
}

.code-lang {
    font-size: 0.7rem;
    color: var(--accent);
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.3px;
}

.code-copy {
    background: none;
    border: 1px solid var(--border);
    color: var(--text2);
    padding: 2px 12px;
    border-radius: 6px;
    font-size: 0.7rem;
    cursor: pointer;
    font-weight: 600;
    transition: 0.15s;
}

.code-copy:hover {
    border-color: var(--accent);
    color: var(--accent);
}

.code-body {
    padding: 16px 18px;
    overflow-x: auto;
    font-family: var(--mono);
    font-size: 0.8rem;
    line-height: 1.8;
    color: var(--text);
    white-space: pre-wrap;
    word-break: break-word;
}

.code-body .kw {
    color: #c678dd;
}

.code-body .str {
    color: #98c379;
}

.code-body .cmt {
    color: #5c6370;
    font-style: italic;
}

.code-body .type {
    color: #e5c07b;
}

.code-body .fn {
    color: #61afef;
}

.code-body .ann {
    color: #56b6c2;
}

.code-body .num {
    color: #d19a66;
}

.code-body .highlight {
    background: rgba(79, 124, 255, 0.15);
    padding: 0 4px;
    border-radius: 4px;
    border-left: 2px solid var(--accent);
}

.inline-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    background: var(--bg3);
    border-radius: 50%;
    width: 22px;
    height: 22px;
    border: 1px solid var(--border);
    margin-right: 4px;
}

/* Tip */
.tip {
    display: flex;
    gap: 12px;
    padding: 12px 16px;
    background: var(--accent-dim);
    border: 1px solid rgba(79, 124, 255, 0.2);
    border-radius: var(--r);
    margin: 18px 0 8px;
    font-size: 0.85rem;
    color: var(--accent);
    align-items: flex-start;
}

.tip svg {
    flex-shrink: 0;
    margin-top: 3px;
}

.tip.green {
    background: var(--green-dim);
    border-color: rgba(52, 211, 153, 0.2);
    color: var(--green);
}

/* Success */
.done-banner {
    text-align: center;
    margin-top: 40px;
    padding: 28px 20px;
    background: var(--green-dim);
    border: 1px solid rgba(52, 211, 153, 0.2);
    border-radius: var(--r);
    opacity: 0;
    animation: fadeIn 0.5s 0.9s forwards;
}

.done-banner h3 {
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--green);
    margin-bottom: 6px;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
}

.done-banner p {
    color: var(--text2);
    font-size: 0.9rem;
}

.back {
    display: block;
    text-align: center;
    margin-top: 28px;
    color: var(--text2);
    text-decoration: none;
    font-size: 0.9rem;
    transition: 0.15s;
}

.back:hover {
    color: var(--accent);
}

@media (max-width: 480px) {
    .step {
        padding-left: 44px;
    }

    .step-num {
        width: 32px;
        height: 32px;
        font-size: 0.8rem;
        top: 22px;
    }

    .header h1 {
        font-size: 1.4rem;
    }

    .code-body {
        font-size: 0.7rem;
        padding: 12px;
    }

    .sidebar {
        width: 260px;
    }
}