/* ── Light theme (default) ── */
:root {
    --bg: #f5f5f5;
    --card-bg: #ffffff;
    --card-shadow: 0 4px 24px rgba(0, 0, 0, 0.08);
    --text-primary: #18181b;
    --text-secondary: #71717a;
    --input-bg: #f4f4f5;
    --input-border: #e4e4e7;
    --input-focus-border: #10b981;
    --input-focus-ring: rgba(16, 185, 129, 0.18);
    --input-text: #18181b;
    --input-placeholder: #a1a1aa;
    --btn-bg: #18181b;
    --btn-text: #ffffff;
    --btn-hover-bg: #27272a;
    --error-bg: #fef2f2;
    --error-text: #dc2626;
    --error-border: #fecaca;

    /* Custom easing — built-in CSS easings are too weak */
    --ease-out: cubic-bezier(0.23, 1, 0.32, 1);
    --ease-in-out: cubic-bezier(0.77, 0, 0.175, 1);
}

/* ── Dark theme ── */
[data-theme="dark"] {
    --bg: #09090b;
    --card-bg: #18181b;
    --card-shadow: 0 4px 24px rgba(0, 0, 0, 0.4);
    --text-primary: #fafafa;
    --text-secondary: #a1a1aa;
    --input-bg: #27272a;
    --input-border: #3f3f46;
    --input-focus-border: #10b981;
    --input-focus-ring: rgba(16, 185, 129, 0.22);
    --input-text: #fafafa;
    --input-placeholder: #71717a;
    --btn-bg: #fafafa;
    --btn-text: #18181b;
    --btn-hover-bg: #e4e4e7;
    --error-bg: #450a0a;
    --error-text: #fca5a5;
    --error-border: #7f1d1d;
}

/* ── Reset & Base ── */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: var(--bg);
    color: var(--text-primary);
    min-height: 100vh;
    -webkit-font-smoothing: antialiased;
}

/* ── Layout ── */
.login-container {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 100vh;
    padding: 20px;
}

.login-card {
    background: var(--card-bg);
    border-radius: 16px;
    box-shadow: var(--card-shadow);
    padding: 40px 32px;
    width: 100%;
    max-width: 400px;

    /* Entrance: scale up from 0.96 with fade */
    opacity: 1;
    transform: scale(1);
    transition: opacity 360ms var(--ease-out), transform 360ms var(--ease-out);
}

@starting-style {
    .login-card {
        opacity: 0;
        transform: scale(0.96);
    }
}

/* Stagger children — fade & lift after the card itself */
.login-header,
#step1 > .form-group,
#step2 > .code-sent-info,
#step2 > .form-group {
    animation: child-in 320ms var(--ease-out) both;
}

.login-header { animation-delay: 60ms; }
#step1 > .form-group { animation-delay: 110ms; }
#step2 > .code-sent-info { animation-delay: 110ms; }
#step2 > .form-group { animation-delay: 160ms; }

@keyframes child-in {
    from { opacity: 0; transform: translateY(6px); }
    to   { opacity: 1; transform: translateY(0); }
}

/* ── Header ── */
.login-header {
    text-align: center;
    margin-bottom: 32px;
}

.login-header h1 {
    font-size: 24px;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 8px;
    letter-spacing: -0.01em;
}

.login-subtitle {
    font-size: 14px;
    color: var(--text-secondary);
}

/* ── Form ── */
.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    font-size: 14px;
    font-weight: 500;
    color: var(--text-primary);
    margin-bottom: 6px;
}

.form-group input:not(.otp-digit) {
    width: 100%;
    padding: 12px 14px;
    font-size: 15px;
    color: var(--input-text);
    background: var(--input-bg);
    border: 1px solid var(--input-border);
    border-radius: 10px;
    outline: none;
    box-shadow: 0 0 0 0 var(--input-focus-ring);
    transition:
        border-color 160ms var(--ease-out),
        box-shadow 200ms var(--ease-out),
        background-color 160ms var(--ease-out);
}

.form-group input:not(.otp-digit)::placeholder {
    color: var(--input-placeholder);
}

.form-group input:not(.otp-digit):hover:not(:focus) {
    border-color: color-mix(in srgb, var(--input-border) 60%, var(--text-secondary));
}

.form-group input:not(.otp-digit):focus {
    border-color: var(--input-focus-border);
    box-shadow: 0 0 0 4px var(--input-focus-ring);
}

/* ── Error message ── */
.error-message {
    background: var(--error-bg);
    color: var(--error-text);
    border: 1px solid var(--error-border);
    border-radius: 10px;
    padding: 12px 14px;
    font-size: 14px;
    margin-bottom: 20px;
}

.error-message:not(.hidden) {
    animation: error-in 220ms var(--ease-out);
}

@keyframes error-in {
    from { opacity: 0; transform: translateY(-4px); }
    to   { opacity: 1; transform: translateY(0); }
}

/* ── Submit button ── */
.btn-login {
    width: 100%;
    padding: 14px;
    font-size: 15px;
    font-weight: 600;
    color: var(--btn-text);
    background: var(--btn-bg);
    border: none;
    border-radius: 10px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    transform: scale(1);
    transition:
        background-color 160ms var(--ease-out),
        transform 160ms var(--ease-out),
        opacity 200ms var(--ease-out),
        box-shadow 200ms var(--ease-out);
}

@media (hover: hover) and (pointer: fine) {
    .btn-login:hover:not(:disabled) {
        background: var(--btn-hover-bg);
    }
}

.btn-login:active:not(:disabled) {
    transform: scale(0.97);
}

.btn-login:focus-visible {
    box-shadow: 0 0 0 3px var(--input-focus-ring);
}

.btn-login:disabled {
    opacity: 0.6;
    cursor: not-allowed;
}

/* ── Spinner ── */
.spinner {
    width: 18px;
    height: 18px;
    border: 2px solid transparent;
    border-top-color: var(--btn-text);
    border-radius: 50%;
    animation: spin 0.5s linear infinite;
}

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

/* ── Utility ── */
.hidden {
    display: none !important;
}

/* ── OTP step 2 ── */
.code-sent-info {
    text-align: center;
    margin-bottom: 24px;
}

.code-sent-text {
    font-size: 14px;
    color: var(--text-secondary);
    margin-bottom: 8px;
}

.code-sent-text strong {
    color: var(--text-primary);
}

.link-btn {
    background: none;
    border: none;
    color: var(--input-focus-border);
    font-size: 14px;
    cursor: pointer;
    padding: 4px 0;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 44px;
    text-decoration: underline;
    transition: opacity 160ms var(--ease-out), transform 160ms var(--ease-out);
}

@media (hover: hover) and (pointer: fine) {
    .link-btn:hover {
        opacity: 0.8;
    }
}

.link-btn:active:not(:disabled) {
    opacity: 0.6;
    transform: scale(0.98);
}

.resend-btn {
    display: flex;
    width: 100%;
    text-align: center;
    margin-top: 16px;
    text-decoration: none;
    color: var(--text-secondary);
}

.resend-btn:not(:disabled) {
    color: var(--input-focus-border);
    cursor: pointer;
    text-decoration: underline;
}

.resend-btn:disabled {
    cursor: not-allowed;
    opacity: 0.7;
}

/* OTP digit boxes */
.otp-inputs {
    display: flex;
    gap: 8px;
    justify-content: center;
}

.otp-digit {
    width: 48px;
    height: 56px;
    text-align: center;
    font-size: 24px;
    font-weight: 600;
    color: var(--input-text);
    background: var(--input-bg);
    border: 1px solid var(--input-border);
    border-radius: 10px;
    outline: none;
    caret-color: transparent;
    box-shadow: 0 0 0 0 var(--input-focus-ring);
    transform: scale(1);
    transition:
        border-color 160ms var(--ease-out),
        box-shadow 200ms var(--ease-out),
        background-color 160ms var(--ease-out),
        transform 200ms var(--ease-out);
}

.otp-digit:focus {
    border-color: var(--input-focus-border);
    box-shadow: 0 0 0 4px var(--input-focus-ring);
}

/* "Has value" affordance — subtle scale + accent border */
.otp-digit:not(:placeholder-shown),
.otp-digit[data-filled="true"] {
    border-color: var(--input-focus-border);
    background: color-mix(in srgb, var(--input-bg) 80%, var(--input-focus-border));
}

/* ── Mobile adjustments ── */
@media (max-width: 480px) {
    .login-card {
        padding: 32px 24px;
        border-radius: 12px;
    }

    .login-header h1 {
        font-size: 22px;
    }

    .otp-digit {
        width: 42px;
        height: 48px;
        font-size: 20px;
    }

    .otp-inputs {
        gap: 6px;
    }
}

/* ── Reduced motion ── */
@media (prefers-reduced-motion: reduce) {
    .login-card,
    .login-card > *,
    .login-card > * > *,
    .btn-login,
    .otp-digit,
    .form-group input:not(.otp-digit),
    .link-btn {
        transition-duration: 0ms !important;
        transform: none !important;
        animation-duration: 0ms !important;
    }

    .error-message:not(.hidden) {
        animation: none;
    }

    .spinner {
        animation-duration: 1s;
    }
}