:root {
    --bg: linear-gradient(135deg, #f1f5f9 0%, #e2e8f0 50%, #cbd5e1 100%);
    --surface: rgba(255, 255, 255, 0.95);
    --surface-glass: rgba(255, 255, 255, 0.85);
    --border: rgba(71, 85, 105, 0.2);
    --border-glow: rgba(79, 70, 229, 0.4);
    --text: #1e293b;
    --text-muted: #475569;
    --primary: linear-gradient(135deg, #6366f1 0%, #8b5cf6 100%);
    --primary-glow: rgba(99, 102, 241, 0.3);
    --radius-ctl: 12px;
    --shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.15), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    --shadow-sm: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --focus: 0 0 0 3px rgba(79, 70, 229, 0.3);
    --glass-border: 1px solid rgba(71, 85, 105, 0.2);
    --backdrop-blur: blur(12px);
}

@media (prefers-color-scheme: dark) {
    :root {
        --bg: linear-gradient(135deg, #0f172a 0%, #1e293b 50%, #334155 100%);
        --surface: rgba(30, 41, 59, 0.9);
        --surface-glass: rgba(30, 41, 59, 0.8);
        --border: rgba(148, 163, 184, 0.2);
        --text: #f1f5f9;
        --text-muted: #94a3b8;
        --shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.4);
        --shadow-sm: 0 10px 15px -3px rgba(0, 0, 0, 0.2);
        --glass-border: 1px solid rgba(148, 163, 184, 0.15);
    }
}

* {
    box-sizing: border-box;
}

body {
    background: var(--bg);
    background-attachment: fixed;
    color: var(--text);
    font-family: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, Ubuntu, Cantarell, "Noto Sans", Arial;
    margin: 0;
    padding: 0;
    min-height: 100vh;
    display: grid;
    place-items: center;
    position: relative;
    overflow: hidden;
}

body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: 
        radial-gradient(600px circle at 30% 40%, rgba(99, 102, 241, 0.15) 0%, transparent 50%),
        radial-gradient(800px circle at 70% 60%, rgba(139, 92, 246, 0.1) 0%, transparent 50%);
    pointer-events: none;
    z-index: -1;
}

form {
    background: var(--surface-glass);
    backdrop-filter: var(--backdrop-blur);
    border: var(--glass-border);
    padding: 32px;
    width: 400px;
    max-width: 90vw;
    border-radius: 16px;
    box-shadow: var(--shadow);
    position: relative;
    overflow: hidden;
}

form::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 2px;
    background: var(--primary);
    opacity: 0.8;
}

h2 {
    margin: 0 0 24px 0;
    font-size: 28px;
    font-weight: 700;
    text-align: center;
    background: var(--primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    text-shadow: 0 0 20px var(--primary-glow);
}

input {
    width: 100%;
    height: 48px;
    padding: 0 16px;
    border: 1.5px solid var(--border);
    border-radius: var(--radius-ctl);
    font-size: 16px;
    background: var(--surface-glass);
    backdrop-filter: var(--backdrop-blur);
    color: var(--text);
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    margin-bottom: 16px;
}

input:focus {
    outline: none;
    box-shadow: var(--focus);
    border-color: rgba(165, 180, 252, 0.6);
    background: var(--surface);
}

input::placeholder {
    color: var(--text-muted);
}

button {
    width: 100%;
    height: 48px;
    background: var(--primary);
    color: #ffffff;
    border: none;
    border-radius: var(--radius-ctl);
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: 0 4px 14px 0 var(--primary-glow);
    margin-top: 8px;
}

button:hover {
    box-shadow: 0 6px 20px var(--primary-glow);
    transform: translateY(-2px);
}

button:active {
    transform: translateY(0) scale(0.98);
}

.error {
    background: rgba(239, 68, 68, 0.1);
    color: #ef4444;
    border: 1px solid rgba(239, 68, 68, 0.3);
    padding: 12px 16px;
    border-radius: var(--radius-ctl);
    margin-bottom: 20px;
    font-size: 14px;
    text-align: center;
    backdrop-filter: var(--backdrop-blur);
}