:root {
    --bg: #f2f2f7;
    --card-bg: rgba(255, 255, 255, 0.72);
    --card-border: rgba(255, 255, 255, 0.6);
    --text: #1c1c1e;
    --text-secondary: #8e8e93;
    --accent: #007aff;
    --accent-press: #0062cc;
    --success: #34c759;
    --danger: #ff3b30;
    --field-bg: #ffffff;
    --field-border: #e5e5ea;
    --radius: 16px;
    --shadow: 0 8px 30px rgba(0, 0, 0, 0.06);
}

@media (prefers-color-scheme: dark) {
    :root {
        --bg: #000000;
        --card-bg: rgba(28, 28, 30, 0.72);
        --card-border: rgba(84, 84, 88, 0.36);
        --text: #ffffff;
        --text-secondary: #98989f;
        --field-bg: #1c1c1e;
        --field-border: #38383a;
    }
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    -webkit-tap-highlight-color: transparent;
}

html {
    -webkit-text-size-adjust: 100%;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", "SF Pro",
        "Helvetica Neue", "PingFang SC", "Microsoft YaHei", sans-serif;
    background: var(--bg);
    color: var(--text);
    min-height: 100vh;
    min-height: 100dvh;
    line-height: 1.5;
    -webkit-font-smoothing: antialiased;
}

.container {
    max-width: 480px;
    margin: 0 auto;
    padding: calc(env(safe-area-inset-top) + 32px) 20px
        calc(env(safe-area-inset-bottom) + 32px);
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.hero {
    text-align: center;
    padding: 16px 0 4px;
}

.logo {
    font-size: 52px;
    line-height: 1;
    margin-bottom: 12px;
}

.hero h1 {
    font-size: 28px;
    font-weight: 700;
    letter-spacing: -0.02em;
}

.subtitle {
    margin-top: 8px;
    font-size: 15px;
    color: var(--text-secondary);
}

.card {
    background: var(--card-bg);
    backdrop-filter: saturate(180%) blur(20px);
    -webkit-backdrop-filter: saturate(180%) blur(20px);
    border: 1px solid var(--card-border);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    padding: 20px;
}

.field {
    margin-bottom: 16px;
}

.field label {
    display: block;
    font-size: 13px;
    font-weight: 600;
    color: var(--text-secondary);
    margin-bottom: 8px;
    padding-left: 2px;
}

.field input {
    width: 100%;
    /* 16px 防止 iOS Safari 聚焦时自动放大 */
    font-size: 16px;
    font-family: inherit;
    color: var(--text);
    background: var(--field-bg);
    border: 1px solid var(--field-border);
    border-radius: 12px;
    padding: 14px 16px;
    transition: border-color 0.2s ease, box-shadow 0.2s ease;
    appearance: none;
}

.field input::placeholder {
    color: var(--text-secondary);
    opacity: 0.7;
}

.field input:focus {
    outline: none;
    border-color: var(--accent);
    box-shadow: 0 0 0 3px rgba(0, 122, 255, 0.15);
}

.message {
    font-size: 14px;
    margin-bottom: 14px;
    padding: 10px 14px;
    border-radius: 10px;
}

.message.error {
    color: var(--danger);
    background: rgba(255, 59, 48, 0.1);
}

.message.success {
    color: var(--success);
    background: rgba(52, 199, 89, 0.12);
}

.btn-primary {
    width: 100%;
    font-size: 17px;
    font-weight: 600;
    font-family: inherit;
    color: #fff;
    background: var(--accent);
    border: none;
    border-radius: 14px;
    padding: 15px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    transition: transform 0.1s ease, background 0.2s ease, opacity 0.2s ease;
}

.btn-primary:active {
    transform: scale(0.98);
    background: var(--accent-press);
}

.btn-primary:disabled {
    opacity: 0.6;
    cursor: default;
}

.btn-secondary {
    width: 100%;
    font-size: 16px;
    font-weight: 600;
    font-family: inherit;
    color: var(--accent);
    background: rgba(0, 122, 255, 0.1);
    border: none;
    border-radius: 14px;
    padding: 13px;
    margin-top: 16px;
    cursor: pointer;
    transition: transform 0.1s ease, background 0.2s ease;
}

.btn-secondary:active {
    transform: scale(0.98);
    background: rgba(0, 122, 255, 0.18);
}

.spinner {
    width: 18px;
    height: 18px;
    border: 2px solid rgba(255, 255, 255, 0.4);
    border-top-color: #fff;
    border-radius: 50%;
    animation: spin 0.7s linear infinite;
}

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

.result {
    text-align: center;
    animation: pop 0.3s ease;
}

@keyframes pop {
    from { opacity: 0; transform: translateY(8px) scale(0.98); }
    to { opacity: 1; transform: translateY(0) scale(1); }
}

.result-icon {
    width: 52px;
    height: 52px;
    margin: 0 auto 12px;
    border-radius: 50%;
    background: var(--success);
    color: #fff;
    font-size: 28px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.result h2 {
    font-size: 20px;
    font-weight: 700;
}

.result-hint {
    font-size: 14px;
    color: var(--text-secondary);
    margin-top: 6px;
}

.result-link {
    display: block;
    word-break: break-all;
    font-size: 16px;
    color: var(--accent);
    text-decoration: none;
    background: var(--field-bg);
    border: 1px solid var(--field-border);
    border-radius: 12px;
    padding: 14px 16px;
    margin-top: 12px;
}

.footer {
    text-align: center;
    font-size: 12px;
    color: var(--text-secondary);
    margin-top: 8px;
}